Weather Modification
silver iodide   Weather Control Or Modification Patents

 

There is a need to educate people on the dangers weather modification presents for people living today ,and future generations.

First, and foremost, people have to realize weather modification is not something going to take place in the future. Weather modification/geo-engineering  is and has been going on above our heads for decades...

Second, people have a right to know what chemicals are being dumped in the air we breathe in 24/7.

It's time to wake-up to some nasty truths! You may think 'oh, but it says  the stuff they are putting in the sky isn't dangerous.'   I will document the dangers to human health that weather modification is/has created.... Right now, it's important to know what weather modification  is..... Jan Tetstone

[Senate Hearing 109-446]
[From the U.S. Government Printing Office]

S. Hrg. 109-446

WEATHER MODIFICATION AND S. 517, THE WEATHER MODIFICATION RESEARCH AND
TECHNOLOGY TRANSFER AUTHORIZATION ACT OF 2005

=======================================================================

HEARING

before the

SUBCOMMITTEES ON: SCIENCE AND SPACE; DISASTER PREVENTION AND PREDICTION

OF THE

COMMITTEE ON COMMERCE,
SCIENCE, AND TRANSPORTATION
UNITED STATES SENATE

ONE HUNDRED NINTH CONGRESS

FIRST SESSION

__________

NOVEMBER 10, 2005

__________

Printed for the use of the Committee on Commerce, Science, and
Transportation



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_____________________________________________________________________________
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SENATE COMMITTEE ON COMMERCE, SCIENCE, AND TRANSPORTATION

ONE HUNDRED NINTH CONGRESS

FIRST SESSION

TED STEVENS, Alaska, Chairman
JOHN McCAIN, Arizona DANIEL K. INOUYE, Hawaii, Co-
CONRAD BURNS, Montana Chairman
TRENT LOTT, Mississippi JOHN D. ROCKEFELLER IV, West
KAY BAILEY HUTCHISON, Texas Virginia
OLYMPIA J. SNOWE, Maine JOHN F. KERRY, Massachusetts
GORDON H. SMITH, Oregon BYRON L. DORGAN, North Dakota
JOHN ENSIGN, Nevada BARBARA BOXER, California
GEORGE ALLEN, Virginia BILL NELSON, Florida
JOHN E. SUNUNU, New Hampshire MARIA CANTWELL, Washington
JIM DeMINT, South Carolina FRANK R. LAUTENBERG, New Jersey
DAVID VITTER, Louisiana E. BENJAMIN NELSON, Nebraska
MARK PRYOR, Arkansas
Lisa J. Sutherland, Republican Staff Director
Christine Drager Kurth, Republican Deputy Staff Director
David Russell, Republican Chief Counsel
Margaret L. Cummisky, Democratic Staff Director and Chief Counsel
Samuel E. Whitehorn, Democratic Deputy Staff Director and General
Counsel
Lila Harper Helms, Democratic Policy Director
------

SUBCOMMITTEE ON SCIENCE AND SPACE

KAY BAILEY HUTCHISON, Texas, Chairman
TED STEVENS, Alaska BILL NELSON, Florida, Ranking
CONRAD BURNS, Montana JOHN D. ROCKEFELLER IV, West
TRENT LOTT, Mississippi Virginia
JOHN ENSIGN, Nevada BYRON L. DORGAN, North Dakota
GEORGE ALLEN, Virginia E. BENJAMIN NELSON, Nebraska
JOHN E. SUNUNU, New Hampshire MARK PRYOR, Arkansas

SUBCOMMITTEE ON DISASTER PREVENTION AND PREDICTION

JIM DeMINT, South Carolina, Chairman
TED STEVENS, Alaska E. BENJAMIN NELSON, Nebraska,
GORDON H. SMITH, Oregon Ranking
DAVID VITTER, Louisiana MARIA CANTWELL, Washington
BILL NELSON, Florida


C O N T E N T S

----------
Page
Hearing held on November 10, 2005................................ 1
Statement of Senator DeMint...................................... 1
Statement of Senator Hutchison................................... 18

Witnesses

DeFelice, Dr. Thomas P., Past President, Weather Modification
Association.................................................... 7
Prepared statement........................................... 8
Garstang, Michael, Ph.D., Professor, University of Virginia;
Chair, Committee on Critical Issues in Weather Modification
Research, National Research Council of the National Academies.. 10
Prepared statement........................................... 12
Golden, Dr. Joseph H., Senior Research Scientist, Cooperative
Institute for Research in the Environmental Sciences (CIRES),
University of Colorado......................................... 3
Prepared statement........................................... 5

Appendix

Marburger, III, John H., Director, Executive Office of the
President, Office of Science and Technology Policy, letter,
dated December 13, 2005 to Hon. Kay Bailey Hutchison........... 29
Nelson, Hon. E. Benjamin, U.S. Senator from Nebraska, prepared
statement...................................................... 27
Response to written questions submitted to Dr. Thomas P. DeFelice
by:
Hon. Daniel K. Inouye........................................ 33
Hon. E. Benjamin Nelson...................................... 33
Hon. Bill Nelson............................................. 34
Response to written questions submitted to Michael Garstang,
Ph.D., by:
Hon. Daniel K. Inouye........................................ 35
Hon. E. Benjamin Nelson...................................... 35
Hon. Bill Nelson............................................. 35
Response to written questions submitted to Dr. Joseph H. Golden
by:
Hon. Daniel K. Inouye........................................ 30
Hon. E. Benjamin Nelson...................................... 31
Hon. Bill Nelson............................................. 32
Wilhite, Dr. Donald, Director, National Drought Mitigation
Center, University of Nebraska-Lincoln, prepared statement..... 27


WEATHER MODIFICATION AND S. 517, THE WEATHER MODIFICATION RESEARCH AND
TECHNOLOGY TRANSFER AUTHORIZATION ACT OF 2005

----------


THURSDAY, NOVEMBER 10, 2005

U.S. Senate,
Subcommittees on: Science and Space; Disaster
Prevention and Prediction,
Committee on Commerce, Science, and Transportation,
Washington, DC.
The Subcommittees met, pursuant to notice, at 2:30 p.m. in
room SD-562, Dirksen Senate Office Building, Hon. Jim DeMint,
presiding.

OPENING STATEMENT OF HON. JIM DeMINT,
U.S. SENATOR FROM SOUTH CAROLINA

Senator DeMint. Good afternoon. Sorry for the confusion. I
appreciate all of you folks joining us this afternoon and look
forward to hearing from you. My other chairman of this meeting,
Senator Hutchison, will be back in just a moment. And I know
she's been a part of inviting this group here today.
I am very interested in the testimony. We saw, numerous
times this summer, and just this past weekend, in Indiana and
Kentucky, that weather has a profound impact on the lives of
Americans. And this afternoon, the Subcommittees will be
discussing weather modification, and, specifically, legislation
introduced by my colleague, Senator Hutchison, Senate bill 517,
the Weather Modification Research and Technology Transfer
Authorization Act.
As I understand, the genesis of this legislation was to
help provide relief to drought-stricken farmers in West Texas
and across the Nation. As we are all aware, weather
modification technologies have been pursued for a number of
years. For decades, the Federal Government has dedicated
significant resources to weather modification research, and
State and local governments continue to spend millions on both
operational weather modification technologies and weather
modification research.
I was interested to learn that recently the National
Research Council of the National Academies, the Nation's
leading scientific body, raised some concerns about efficacy of
weather modification research. Because of the importance of
this issue, I'm looking forward to Dr. Garstang's comments this
afternoon and his assessment of the state of the science
surrounding weather modification research. It's entirely
possible that, at some point in the future, weather
modification technologies might be viable. I continue to be
impressed by the progress of all kinds of American innovations.
At some point, this Committee may get to the point where it is
considering the complex legal, social, and political issues
surrounding whether or not the Nation should support a regimen
of weather modification. But I am aware there are serious
concerns about pursuing a regimen of intentional weather
modification and want to give those concerns careful
consideration.
I'm also concerned that, as a Nation, we do not have
sufficient understanding of how our atmosphere behaves. It
seems that this may be a concern shared by the Academy, noting
some of the findings in their recent report. I think this
Committee should give thoughtful consideration to their
principal conclusion, which stated that, ``Atmospheric science
is now in a position to mount a concerted and sustained effort
to delineate the scope and expectations of future weather
modification research. Such an effort must be directed at
answering fundamental scientific questions that will yield
results that will go well beyond application to intentional
modification. The emphasis must be on understanding processes,
and not on modification.'' I think--in other words, I believe
what I'm hearing them saying is that we need to understand how
weather works now before we go too far in trying to modify it.
I would also encourage the scientific community, and
particularly the atmospheric-sciences community, through the
National Academies or our scientific societies, to decide what
are the highest priorities and most promising areas of research
for fundamental atmospheric research. The NRC report on weather
modification research outlines some areas that may inform
weather modification, such as precipitation physics and cloud
modeling. Could these areas or other areas of the research be
considered as part of a comprehensive program of atmospheric
research? I'll let you answer the question today.
Priority-setting is going to be important. In recent years,
Republicans in Washington have endeavored to constrain Federal
spending. We've not been as successful as I would like, but I'm
committed to working with my colleagues to ensure that Federal
discretionary spending not only does not grow, but that it
shrinks.
I say all this to encourage the atmospheric-science
community to think critically about where you want to put the
next dollar in atmospheric research. There are some very
promising places to put this funding that could have a dramatic
impact on the lives of all Americans. I would encourage you to
consider the various research initiatives proposed by the
Academy in light of the other important initiatives that need
to be undertaken to improve prediction of tornado formation, to
understand the rapid intensification of hurricanes, and the
other challenges facing us.
How do all of these competing priorities interact? Maybe
there is some overlap that will address these important issues
and inform weather modification. I hope the scientific
community can help me and this Committee with this priority-
setting.
This Committee is committed to advancing atmospheric
sciences, because we understand what an important role weather
plays in the lives of all Americans. So, I'm looking forward to
hearing from you. This issue leaves me with a lot of questions,
and I'm hoping my witnesses can answer some of those questions
today.
Appearing this afternoon is Dr. Joe Golden, Senior Research
Scientist at Colorado's Cooperative Institute for Research in
the Environmental Sciences. Dr. Golden previously directed
NOAA's weather modification research programs. He will discuss
Senate bill 517 and its potential benefits for weather
modification.
Also with us is Dr. Tom DeFelice, past President of the
National Weather Modification Association. He will be providing
perspectives on the importance of weather modification and
weather modification research.
Finally, appearing before the Subcommittees this afternoon,
is Dr. Michael Garstang. Dr. Garstang is a Distinguished
Emeritus Research Professor in the Department of Environmental
Sciences, at the University of Virginia. He's a fellow at the
American Meteorological Society, the AMS--and has served on
numerous AMS committees. He was also the Chair of the 2003
National Research Council Committee on Critical Issues in
Weather Modification Research.
OK, having introduced all of our panelists, Dr. Golden,
we'll start with you, and if Senator Hutchison comes in, we may
need to take a break and let her make a statement if she can't
stay the whole time.
So, Dr. Golden, please--I think we're going to try to keep
this to five minutes, and then some questions.

STATEMENT OF DR. JOSEPH H. GOLDEN, SENIOR RESEARCH SCIENTIST,
COOPERATIVE INSTITUTE FOR RESEARCH IN THE ENVIRONMENTAL
SCIENCES (CIRES), UNIVERSITY OF COLORADO

Dr. Golden. Thank you, Senator DeMint.
I am honored to appear before you today in regards to
Senate bill 517, the Weather Modification Research and
Technology Transfer Authorization Act of 2005. My name is Dr.
Joseph Golden, retired from NOAA on September 2, 2005, after
over 41 years of Federal service in NOAA, both in severe-
weather research and NWS operations. I now work part-time as a
Senior Research Scientist in the University of Colorado's
Cooperative Institute, in Boulder, Colorado.
My background in weather modification research relates to
the fact that I was the last NOAA manager of the Atmospheric
Modification Program, or AMP, in NOAA research until its
termination by the Congress in 1995. None of the NOAA AMP funds
were used to conduct any operational cloud-seeding, and I feel
that, at this time, funding under Senate bill 517 should also
not be used to conduct any operational cloud-seeding.
The Texas participation in my AMP program was the first to
utilize the NWS NEXRAD Doppler radar data to estimate the
rainfall increases from seeding convective clouds in Texas.
However, one of my greatest career frustrations has been
witnessing the adoption of new research results and
technologies, that we developed under AMP, by other countries,
while our Federal research and technology transfer in my
country has largely stagnated.
One example, a chemical tracer technique that we developed
in my Nevada AMP program to quantify the amount of snow
increase due to seeding over mountains is now being used by a
new cloud-seeding program in Australia.
In China alone, their government is now funding a greatly
expanded weather modification research and operations program
at $100 million per year, as well as training over 1,500 new
weather modification scientists.
Federal funding for weather modification research in the
United States reached its pinnacle in the 1970s and early
1980s, and has steadily declined ever since. During its heyday,
weather modification research in the U.S. was at the cutting
edge of worldwide efforts. For example, NOAA conducted large-
scale seeding experiments, in South Florida, called FACE, and
we collaborated with the Navy and university scientists in
Project STORMFURY to weaken hurricanes. I participated in
STORMFURY while I was a Ph.D. candidate, and found it to be one
of the most exhilarating experiences of my career.
The need for a renewed national commitment and funding for
weather modification research has become more urgent, in my
view. In recent years, we have seen severe drought in my home
State of Colorado and the Pacific Northwest. New research
results show unmistakable impacts of air pollution in reducing
seasonal precipitation over mountainous areas of the Western
U.S. during the past several decades. Pollution is
systematically robbing the western mountains of winter
snowpack, and, if the process continues, will lead to major
losses of runoff water for hydroelectric power and agricultural
crop productivity. However, research results in Israel--has
demonstrated that their long-term cloud-seeding programs have
offset similar pollution-induced rainfall losses in their
country.
Another weather modification research issue, and one that
elicits scientific controversy, is severe-storms modification.
I don't have time to go into this in any depth, but one of the
longest-running hail-suppression programs in the world is in
North Dakota. And, during my tenure, AMP sponsored their
research. Positive results on the impact of cloud-seeding to
reduce hail damage to crops using insurance companies' records
of crop-loss ratios were so impressive in North Dakota, that
the Canadian insurance industry has supported a new multi-year
effort in the Province of Alberta, Canada, to protect its
largest cities from hail. The Alberta hail-suppression program
uses many of the techniques that we used in the AMP North
Dakota program.
Finally, after the horrendous devastation and loss of life
from Hurricanes Katrina and Rita, I have been asked several
times about the possibility of hurricane modification. And,
while we don't have time to fully address the issue today, I
firmly believe that we are in a much better position, both with
the science and the undergirding technology, than we were when
Project STORMFURY was terminated by our government in 1982. We
now understand that both tornados and hurricanes exhibit a life
cycle, and both exhibit natural instabilities during their
lifetimes.
Even after the demise of the AMP program in 1995,
operational weather modification programs have continued to
expand and flourish in the U.S. This is reflected in the annual
reports of all such projects to NOAA, as required by law.
I like the idea of establishing a Weather Modification
Advisory Board with broad representation, which is needed to
set the national agenda and priorities, as Senator DeMint has
already touched upon, for these and other urgent water-
management issues facing the country. I have many close
scientific colleagues in NOAA weather research who would
welcome the opportunity to contribute to a reinvigorated
national program of weather modification research and
technology transfer.
In closing, I want to assure you that the U.S. has the
technology and the best and brightest scientists, who would
welcome the opportunity to reinvigorate the weather
modification field. These are very challenging issues, and the
worsening water crises in the West and elsewhere demand our
urgent attention.
Thank you.
[The prepared statement of Dr. Golden follows:]

Prepared Statement of Dr. Joseph H. Golden, Senior Research Scientist,
Cooperative Institute for Research in the Environmental Sciences
(CIRES), University of Colorado

I am honored to appear before you today in regards to S. 517, the
Weather Modification Research and Technology Transfer Authorization Act
of 2005. My name is Dr. Joseph H. Golden, retired from NOAA on
September 2, 2005 after 41.5 years of Federal service in NOAA, both in
severe weather research and NWS operations. I now work part-time as a
Senior Research Scientist in the University of Colorado's Cooperative
Institute for Research in the Environmental Sciences (CIRES) in
Boulder, Colorado. My background in weather modification research
relates to the fact that I was the last NOAA manager of the Atmospheric
Modification Program (AMP) in NOAA Research, until its termination by
the Congress in 1995. I was never asked by anyone to defend the AMP
Program, based on its merits and accomplishments. The AMP program was
written into NOAA's budget by the Congress for many years, beginning in
the late 1970s. I view the AMP program and its research productivity as
a highlight of my NOAA career, especially due to the cooperative
efforts among the six States in the program (Illinois, North Dakota,
Texas, Utah, Nevada and Arizona), the universities, private-sector
operators, and NOAA research. None of the NOAA AMP funds were used to
conduct any operational cloud seeding, and I feel that, at this time,
funding under S. 517 should also not be used for operational cloud
seeding efforts. I am pleased to see my colleague, George Bomar here
from Texas: he was one of the State program managers in AMP, and his
State was the first to utilize NWS NEXRAD Doppler radar data to
estimate the rainfall increases from seeding convective clouds. One of
my greatest career frustrations has been witnessing the adoption of new
research results and technologies we developed under AMP by other
countries, while Federal research and technology transfer in my own
country has largely stagnated. For example, a chemical tracer technique
developed by the Nevada-AMP program to quantify the amount of snow
increase due to seeding over mountains is now being used by a new cloud
seeding program in Australia. In China alone, their government is
funding a greatly-expanded weather modification research and operations
program at $100 million per year, as well as training over 1,500 new
weather modification scientists.
In the limited time I speak before you today, I want to address two
types of natural disasters, and the potential for planned weather
modification to alleviate them: slow-onset disasters over many years,
such as the continuing drought in the West, and the quick-onset
disasters such as the record-breaking Atlantic hurricane season this
year and the massive Oklahoma City tornado outbreak of May 1999.
Federal funding for weather modification research in the U.S.
reached its pinnacle in the 1970s and early 1980s, and has steadily
declined ever since. During its heyday, weather modification research
in the U.S. was at the cutting edge of worldwide efforts. For example,
NOAA conducted large-scale seeding experiments in South Florida (called
FACE) and collaborated with the Navy and university scientists in
Project STORMFURY, to weaken hurricanes. I participated in STORMFURY
while a Ph.D candidate, and found it to be one of most exhilarating
experiences of my career. The National Center for Atmospheric Research
(NCAR) also organized the National Hail Research Experiment, which
attempted to test the validity of the Russian approach to artificially
reduce hail by cloud seeding. Finally, the Bureau of Reclamation
carried out the High Plains experiment, to seed convective clouds for
rainfall increases over the Central U.S. While each of these programs,
in my opinion, produced outstanding scientific results and new
operational insights, they produced results that were inconclusive
insofar as statistical evaluation is concerned. Nevertheless, I feel
that our community was a good steward and used limited funding very
wisely. I am also convinced that the atmospheric sciences have come a
long way during the intervening years. The scientific foundation and
underlying physics in purposeful weather modification, i.e., cloud
seeding, is sound and well-established. We now have both the science
and the technology to launch a new research attack on some of these
other vexing problems.
The need for a renewed national commitment and funding for weather
modification research has become more urgent. In recent years, we have
seen severe drought in my home State of Colorado and the Pacific
Northwest. New research results show unmistakable impacts of air
pollution in reducing seasonal precipitation over mountainous areas of
the Western U.S. during the past several decades. Pollution is
systematically robbing the Western mountains of winter snowpack, and if
the process continues, will lead to major losses of runoff water for
hydroelectric power and agricultural crop productivity. However,
research in Israel has demonstrated that their long-term cloud seeding
programs have offset similar pollution-induced rainfall losses in their
country. The new research has also developed new analysis techniques
with NOAA satellite data to objectively identify and separate pollution
episodes from affected neighboring clouds. The pollution effects on
natural precipitation in our country and elsewhere is certainly a
critical research issue for this bill. Another issue needing more
research attention is the question of extra-area effects: if we seed
cloud systems in one area, and successfully produce increases of
precipitation there, are we ``robbing Peter to pay Paul'' in downwind
locations? Results supported by AMP suggested the answer is no, and
that there is either no effect downwind, or a slight increase in
precipitation.
Another weather modification research issue, and one that always
elicits scientific controversy, is severe storms modification. This
issue was not addressed much in the NAS/NRC weather modification report
chaired by my distinguished colleague, Michael Garstang. These are the
quick-onset disasters of which I spoke earlier, and include hailstorms,
tornadoes and hurricanes like Katrina and Rita this year. I should
emphasize that AMP supported some outstanding hail modification
research with the North Dakota Cloud Modification Program. This
operational program is one of the longest-running hail suppression
programs in the world. Positive results on the impact of cloud-seeding
to reduce hail damage to crops, using insurance companies' records of
crop-loss ratios, were so impressive, that the Canadian insurance
industry has supported a new multi-year effort in the province of
Alberta, Canada to protect its largest cities from hail. The Alberta
hail-suppression program uses many of the techniques that we used in
the AMP-North Dakota program.
After the horrendous devastation and loss of life from Hurricanes
Katrina and Rita, I have been asked several times about the
possibilility of hurricane modification. And while I don't have the
time to fully address this issue today, I firmly believe that we are in
a much better position, both with the science and the undergirding
technology, than we were when Project STORMFURY was terminated in 1982.
We now understand that both tornadoes and hurricanes exhibit a life-
cycle, and both exhibit natural instabilities during their lifetimes.
The key atmospheric condition leading to the decay of both destructive
vortices is cooler, drier air, as well as cooling sea surface
conditions for decaying hurricanes. Recent observational and modeling
studies both suggest that there may be new approaches possible for
future weakening or track-diversion of hurricanes threatening our
shoreline. The key uncertainty, and one which requires enhanced
observations, is more continuous and accurate monitoring of the natural
fluctuations in hurricane intensity and path. For example, Wilma
intensified in the western Caribbean overnight from a Category 1 to a
Category 5 hurricane, resulting in the lowest pressure ever measured in
the eye of an Atlantic-basin hurricane. There are now some very
exciting computer models that reproduce both hurricane intensification
and tornado behavior in remarkable detail. If we mount a sustained,
adequately-funded national program of weather modification research and
technology transfer, I believe that it may also be possible to
successfully weaken tornadoes (or, alternatively, shorten their life-
cycles). I would be pleased to elaborate details on promising
approaches and testable hypotheses for tornado/hurricane amelioration
at some future time. I am presently collaborating with colleagues, Drs.
Rosenfeld and Woodley, in testing a new technique for identifying storm
systems with high threat of producing tornadoes. This technique
utilizes NOAA satellite data at various wavelengths and shows promise
in improving NWS lead-times for tornado watches and warnings.
Even after the demise of the AMP Program in 1995, operational
weather modification programs have continued to expand and flourish in
the U.S. This is reflected in the annual reports of all such projects
to NOAA, as required by law. Most of these projects are supported by
the States, utilities or the private-sector. One of my private-sector
colleagues recently noted his estimate of total annual expenditures in
the U.S. of $25-30 million for weather modification operational
projects. There is now very little Federally-supporting research to aid
these operational programs in evaluation, or improving their
technological base. We have some of the best cutting-edge science in
NOAA research, NCAR and the universities that can help the private
weather modification operators improve their evaluation of seeding
effects, as well as improved targeting of seeding materials in suitable
cloud systems. I like the idea of establishing the Weather Modification
Advisory Board, with broad representation, which is needed to set the
national agenda and priorities for these and other urgent water
management issues facing the country. I have many close scientific
colleagues in NOAA weather research who would welcome the opportunity
to contribute to a reinvigorated national program of weather
modification research and technology transfer, if support can be found.
In fact, our Boulder laboratories won a Department of Commerce Gold
Medal for our contributions to the recently-completed NWS Modernization
and AWIPS computer workstations. I am one who has long believed, that
to be successful in any form of purposeful weather modification, we
must first do a very good job of predicting the natural phenomena.
In closing, I want to assure you that the U.S. has the technology
and the best and brightest scientists who would welcome the opportunity
to reinvigorate the weather modification field. These are very
challenging issues and the worsening water crises in the West and
elsewhere demand our urgent attention.

Senator DeMint. Thank you.
Dr. Defelice?

STATEMENT OF DR. THOMAS P. DeFELICE, PAST PRESIDENT, WEATHER
MODIFICATION ASSOCIATION

Dr. DeFelice. I am honored to appear here today in regards
to Senate bill 517.
My name is Dr. Tom DeFelice. I have two degrees in
atmospheric science, bachelor's in--and Ph.D., and a master's
in atmospheric physics.
I was the WMA President--``WMA'' stands for the Weather
Modification Association--President for 2 years, between 2000
and 2002. I'm now the Chair of the WMA Public Information and
Outreach Committee. I began the process before you today by
engaging a retired State Senator from Texas, John Leedom, who
then engaged Senator Hutchison and her staff.
My experiences and the literature demonstrate that weather
modification technologies generally possess the potential to
increase the rainfall when applied under appropriate
conditions. I don't have time to go into all the details of
those conditions, but will gladly take some questions later.
The scientific and operational communities generally agree
that the recent advances in the relevant general physical
processes and technologies used to assess those processes come
together and form the basis for the need to have a sustained
national program to carry out basic and applied research in
weather modification sciences. This happens to be one of the
main recommendations of the Garstang report.
Basically, I see Senate bill 517 as the next logical step
as one could derive from the Garstang report. It is about
research and development of technologies. But it's not just any
research and any development; it is research and development
that could ultimately be used to produce a product that could
help everybody. It could help commerce, improve better
forecasts of the weather, which could then help our
agricultural entities better plan their crops, for example. It
could help science by improving their models, improving our
understanding of processes, especially those of hurricanes, to
understand why hurricanes like Katrina could form, for example.
But it also could reinvigorate education. It could help
transportation by planning for certain weather events that we
may or may not be able to detect, or take for granted--freezing
rain, icing of roads, for example. Predicting and mitigating
adverse weather conditions in these cases would have a great
benefit, not only to lives, but also to our economies. It could
also help airports in certain circumstances, particularly
during the winter, by clearing out fogs.
Technology could benefit, since the results, information
from this bill could be another application directing its
innovators and be used to transfer said information to the
public. So the research from this bill could also help the
people. And that's what it's all about. Because the people are
faced with an impending water shortage. By the decade of the
2020s, our models predict that 40 percent of the world's
population are going to be living in drought-stressed areas.
And we need to start doing something now about that, because if
we wait, it will be too late, because we haven't been doing the
research to develop and to make sure we have all our ducks in a
row, all our technologies up to par, so that they could be of
some more use (for those that are not useful already). We need
to do something about this, because 8 percent of the total
water budget on the globe is due to consumption, and only 1
percent of the water budget is currently an input. That's rain.
Now, with global warming--and the results of that are predicted
to minimize precipitation falling to the ground--that means by
the decade of the 2020s, or shortly thereafter, less than 1
percent of the total water budget is going to be an input. That
means we're--and with the population growing, we're going to
consume more water, so we're going to have a really, really
grave and--how do I say it?--big problem on our hands, because,
well, there won't be enough water to feed our crops.
And so, I strongly urge everybody--on this Committee and
elsewhere--to consider passing this bill and bringing it to its
companion bill in the House.
[The prepared statement of Dr. DeFelice follows:]

Prepared Statement of Dr. Thomas P. DeFelice, Past President, Weather
Modification Association

I am honored to appear before you today in regards to Senate bill
517, the Weather Modification Research and Technology Transfer
Authorization Act of 2005. My name is Dr. Thomas P. DeFelice. My
background in weather modification began when I was 15 by reading books
on the subject; I had many sessions with WMA forefathers Schaefer &
Vonnegutt as an undergrad; my academic and subsequent professional
career concentrated on learning the fundamentals of weather
modification relevant sciences and its technologies; President of WMA
(2000-2002), Chair WMA Public Information Committee (since 2004). I now
work as the contractor program manager for two NOAA programs. I am here
on my own behalf, expressing my own beliefs. I began this process,
engaged John Leedom, who engaged Senator Hutchison & her staff, and
here we are today.
Weather modification technologies are key to dealing with many
present and potential future scientific, environmental, and
socioeconomic issues like steadily increasing human suffering and
property damage caused by hazardous weather (e.g., severe weather-
Katrina, supercooled fog, freezing rain), fire, and other environmental
problems related to ``acid rain,'' biological or chemical warfare, for
instance. Their application generally increases rainfall amount. Rain
contributes 1 percent of the total global water budget. Global water
consumption presently makes up 8 percent of the total global water
budget. Models estimate about 40 percent of the world's population will
live in water--stressed areas by the decade of the 2020s and
consumption will increase. Further, air pollution (global warming) is
reported to reduce the amount of rainfall. Hence, a need to develop new
technologies, while applying proven techniques. Water rationing and
water management techniques are useful, they do not replenish the
reduced rainwater amount. (They simply put a small band-aid on a wound
that requires multiple stitches.) Therefore they fail to resolve the
issues' root cause. Alternatively, weather modification technologies
increase the rainfall amount (compared to normal) under certain
conditions. (They simply put multiple stitches on a wound that requires
multiple stitches.) Therefore weather modification technologies can
resolve the issues' root cause, which will be ensured through the
research and development program set up by passing S. 517 and its
companion bill (H.R. 2995).
Yet some retain an issue concerning whether operational cloud
seeding activities, especially associated with convective clouds,
achieved the intended results claimed. Additional evaluations should
pacify this issue, especially with the recent technological advances.
This would also help us answer, are weather modification technologies
ready to increase water resources and alleviate, or possibly prevent
drought. Yes, they are ready to increase water resources under certain
cases, based on the available 60-year literature archive, and first-
hand information. S. 517 provides a research and development
infrastructure for a program that addresses and ultimately resolves
these issues, while nurturing and developing these technologies to
provide better returns on our investment.
The scientific and operational communities generally agree that the
recent advances in the relevant, general physical processes and
technologies need to be capitalized upon in the form of a concerted and
sustained national program to carry out basic and applied research in
weather modification (e.g., Garstang report, Orville report, NRC).
However, the perceptions between the science and operational
communities differ, namely, (1) Interpretation of scientific proof, (2)
Current status of cloud models as applied to weather modification, (3)
Evidence of glaciogenic seeding in convective clouds, (4) Cold season
orographic seeding, (5) Evidence for hail suppression, and (6) Support
for specific purposes. The cold season orographic seeding perceptual
difference (4) is not a significant difference in perspective, since
the science community (post Garstang report) sees orographic cloud
seeding as a particularly promising candidate for an intensive field
program.
Perceptual difference (6) reflects the differences between the
individual cultures (i.e., scientific versus operational) than anything
else. Nonetheless, no implementation plans have been proposed.
I summarize an implementation plan for S. 517 for consideration by
its Weather Modification Board, which addresses all issues. This
implementation plan is born from sound scientific basis derived from 60
years of lessons learned exercises, recent technological advances, and
science community recommendations (Garstang report, Orville report,
NRC). Societal need provides an impetus for developing systems and
technologies that monitor and manage atmospheric events, the creation
of a new weather modification research program and implementation plan
according to standard engineering practices. This plan helps mitigate
the perceptual diferences by setting up an integrated team approach to
its activities, and by insisting that its research and development
component be geared toward improving the effectiveness of operations.
It calls for administering the resources and the activities for all
research and development efforts directed toward optimizing the
technologies used to manage atmospheric processes and their resultants
(e.g., collision-coalescence, hurricanes, orographic and convective
precipitation, frozen rain). Its mission would be to develop the
technologies used for operational activities that help provide
sustainable water supplies and reduce airborne hazards. This includes
improving the understanding of the relevant processes and their
simulations, as well as the evaluation methods (physical; chemical;
statistical-random, non-random) for operational activities through
cooperative multidisciplinary research and development arrangements and
a well-designed outreach effort. Further development is needed for
successful application of weather modification technologies to mitigate
hurricane and tornado damage, minimize the negative affects of
anthropogenic air pollution on precipitation efficiency, or to
neutralize negative effects from pollutant deposition. Such requires a
modeling approach, then verification, and transition to operational
use.
The modern weather modification technologies applied to disperse
supercooled fog, augment the ice crystal process in cloud systems,
especially orographic clouds, are very effective. Statistical
reanalysis using 50+ years of Sierra data show strong signals that the
seeding did produce seasonal snowpack increases of 5-10 percent; as
measured by stream runoff data (a conservative surrogate for snowpack
increases). Thus, orographic systems, especially winter orographic
systems, would help maximize S. 517 derived program success. Garstang's
report apparently was unclear on this fact.
The implementation plan does not include less developed
technologies (e.g., extraterrestrial mirrors; ionization, chaos theory-
related approaches; sonic initiation of precipitation, making a
hurricane disappear from conventional radar), or technologies that are
already known to be too costly for the benefits they provide if any
(e.g., using vertical pointing jet engines, or mono-layer films to
suppress moisture flow into hurricanes), based on insufficient
scientific and engineering test results, which pose a significant risk
to programmatic success. The plan does not support funding for Federal
Operational cloud seeding, except for small tests/experiments of new
technologies.
In closing, failure to send S. 517 to appropriate committee
hearings with the companion Udall Bill (H.R. 2995), translates into
desertification, more destructive weather, and even jeopardizes our
standing as the premier scientists, engineers and practitioners in this
area. We have an implementation plan for the program under this bill.
We have the best technology, the brightest personnel to successfully
carry out the implementation plan. The 60 years scientific and
engineering basis helps assure success. Passing S. 517 now, helps avert
adverse efects of desertification, Katrina-like hurricane destruction,
and air pollution effect on the rain process, for example. Thus, this
tax payer fully supports passage of Senate bill S. 517 with a
sufficient budget and duration.

Senator DeMint. Thank you, Doctor.
Dr. Garstang?

STATEMENT OF MICHAEL GARSTANG, Ph.D., PROFESSOR,
UNIVERSITY OF VIRGINIA; CHAIR, COMMITTEE ON CRITICAL ISSUES IN
WEATHER MODIFICATION RESEARCH, NATIONAL RESEARCH COUNCIL OF THE
NATIONAL ACADEMIES

Dr. Garstang. Thank you, Chairman Hutchison and Senator
DeMint.
My name is Michael Garstang. I am a Distinguished Emeritus
Research Professor in the Department of Environmental Sciences
at the University of Virginia. I'm a fellow of the American
Meteorological Society. And I was also Chair of the 2003
National Research Council's Committee on Critical Issues in
Weather Modification Research. The National Research Council is
the operating arm of the National Academies, chartered by
Congress in 1863 to advise the Government on matters of science
and technology.
This afternoon, I will give you a brief summary of the
status of weather modification research as described in our
report. You'll be provided with the executive summary of that
report.
Efforts to minimize harmful weather effects go far back in
time. The first serious scientific efforts in the United States
began in the 1950s. This effort was not sustained. During the
past 30 years, there has been a progressive decline in weather
modification research. Research support related to weather
modification in the United States has dropped to less than a
half a million dollars per year in the year 1999, from a high
of $20 million in the late 1970s.
There have been, concurrently, significant advances in
technology over the past 30 years. This has greatly improved
our ability to observe, understand, and predict the weather.
These advances, however, have not been either collectively or
persistently applied to the problem of weather modification.
This decline in research must--may be the result of a
combination of factors, including early over-optimistic claims,
unrealistic expectations, and a failure to provide
scientifically demonstrable successes. But, despite these
limitations, and because of the considerable pressures that my
colleagues have already indicated resulting from drought, hail,
floods, and storm damage, private and State agencies spend
significant resources to attempt to modify the weather.
In 2001, there were 66 operational weather modification
programs in ten States in the Union, and much more activity
overseas. How do we overcome this disparity between our
willingness to attempt to modify the weather and our reluctance
to fund research to understand such activities?
The NRC's committee concluded that, first, with few
exceptions, there is still no convincing scientific proof of
the efficacy of intentional weather modification. In some
instances, encouraging results have been observed, but this
evidence has not been subjected to adequate testing.
Second, that despite this lack of proof, scientific
understanding has progressed on many fronts. For instance,
there has been substantial improvements in ice-nucleating
capabilities of new seeding materials. Also, new technologies
such as satellite imagery are giving us tools to better
understand microphysical processes that lead to precipitation.
Dr. Golden referred to this. These advantages will help us
focus and optimize weather modification research.
Third, that if progress in establishing our capability to
modify the weather is to be made, the focus must be on key
uncertainties that hamper progress. For example, there are
critical gaps in our understanding of the complex chain of
physical processes that lead to rain, snow, and hail.
The NRC committee's primary recommendation is the
establishment of a coordinated national program of weather
modification research designed to reduce these and other key
uncertainties. The program should consist of a sustained
research effort that uses a balanced approach of modeling,
laboratory studies, and field measurements. Instead of focusing
on near-term operational applications of weather modification,
the program should address fundamental questions. It should
take full advantage of recent related research and advances in
observational, computational, and statistical technologies.
Our Committee--in our--in the Committee's opinion, it is
premature to initiate large operational weather modification
programs. Instead, great opportunity exists to coordinate
research efforts to address fundamental questions that will
lead to credible scientific results. Focused investigation of
atmospheric processes plus coupled technological applications
will advance understanding and bring many unexpected benefits.
This research will place us in a position to determine whether,
how, and to what extent weather systems can be modified.
In conclusion, the NRC committee emphasizes that weather
modification should be viewed as a fundamental and legitimate
part of the atmospheric and environmental science. Growing
demand for fresh water, increasing levels of damage and loss of
life resulting from severe weather, the undertaking of
operational activities without the guidance of a sound
scientific foundation, and the reality of inadvertent
atmospheric changes, the science community now has the
opportunity, the challenge, and the responsibility to assess
the potential efficacy and value of intentional weather
modification.
Thank you for the opportunity to testify. I will be happy
to answer questions.
[The prepared statement of Dr. Garstang follows:]

Prepared Statement of Michael Garstang, Ph.D., Professor, University of
Virginia; Chair, Committee on Critical Issues in Weather Modification
Research, National Research Council of the National Academies

Good afternoon Chairmen Hutchison and DeMint, Ranking Members Bill
Nelson and Ben Nelson, and Members of the Subcommittees. My name is
Michael Garstang, and I am a Distinguished Emeritus Research Professor
in the Department of Environmental Sciences at the University of
Virginia. I'm a fellow of the American Meteorological Society (AMS) and
have served on numerous AMS committees. I was also the chair of the
2003 National Research Council's (NRC) Committee on Critical Issues in
Weather Modification Research. The National Research Council is the
operating arm of the National Academies, chartered by Congress in 1863
to advise the government on matters of science and technology.
This afternoon I will give you a brief summary of the status of
weather modification research, as described in our NRC report, the
major uncertainties that exist, and convey the Committee's conclusions
and recommendations. We will also provide an Executive Summary of the
report which lists the key findings and recommendations in greater
detail.
Efforts to minimize harmful weather impacts go back far in time. In
the last 30 years, significant evidence has accumulated that human
activities unintentionally affect the weather on scales ranging from
local to global. Many of the same fundamental principles underlie both
intentional and unintentional weather modification. Yet during this 30-
year time period, there has been a progressive decline in weather
modification research. Research support related to weather modification
in the United States had dropped to less than $0.5M per year in 1999
from a high of $20M in the late 1970s. During the same period, there
have been significant advances in technology. This has greatly improved
our ability to observe, understand, and predict the weather. These
advances, however, have not been either collectively or persistently
applied to the problem of weather modification.
This decline in research is likely the result of a combination of
factors, including early overly-optimistic claims, unrealistic
expectations, and failure to provide scientifically demonstrable
successes. But despite these limitations, and because of considerable
pressures resulting from drought, hail, floods, and storm damage,
private and state agencies actually spend significant resources on
attempts to modify the weather. In 2001, there were 66 operational
weather modification programs in 10 states and much more activity
overseas.
How do we overcome this disparity between our willingness to
attempt to modify weather and our reluctance to fund research to
understand such activities? The 2003 National Academies committee that
I chaired was charged to provide an updated assessment of the current
state and the future of weather modification research, from new
technologies to advances in numerical modeling and operations. A
summary of our report is included in my written testimony. In my
comments, I want to focus on our conclusions and recommendations.
First, with a few exceptions, the Committee concluded that there
still is no convincing scientific proof of the efficacy of intentional
weather modification efforts. In some instances encouraging results
have been observed, but this evidence has not been subjected to
adequate testing.
Second, despite this lack of proof, the Committee concluded that
scientific understanding has progressed on many fronts. For instance,
there have been substantial improvements in the ice-nucleating
capabilities of new seeding materials. Also, new technologies such as
satellite imagery are giving us tools to better understand the
microphysical processes that lead to precipitation, and these advances,
in time can help focus and optimize weather modification research.
Third, the Committee stated that if progress in establishing our
capability to modify the weather is to be made, intellectual and
technical resources must be brought to bear on the key uncertainties
that hamper progress. For example, there are critical gaps in our
understanding of the complex chain of physical processes that lead to
rain, snow, and hail.
Finally, and most importantly, the Committee called for the
establishment of a coordinated national program of weather modification
research designed to reduce these and other key uncertainties. The
program should consist of a sustained research effort that uses a
balanced approach of modeling, laboratory studies, and field
measurements. Instead of focusing on near-term operational applications
of weather modification, the program should address fundamental
research questions. It should take full advantage of recent related
research and advances in observational, computational, and statistical
technologies, by:

Capitalizing on new remote and in situ observational tools
to carry out exploratory and confirmatory experiments in a
variety of cloud and storm systems;

Improving model treatment of cloud and precipitation
physics;

Improving the use of current computational and data
assimilation methods; and

Capitalizing on existing field facilities and developing
partnerships among research groups and select operational
programs.

In the Committee's opinion, it is premature to initiate large-scale
operational weather modification programs. However, a great opportunity
exists to coordinate research efforts to address the fundamental
questions that will lead to credible scientific results. Focused
investigation of atmospheric processes, coupled with technological
applications, will advance understanding and bring many unexpected
benefits and results. In time, this research will place us in a
position to determine whether, how, and to what extent weather and
weather systems can be modified.
Closing Thoughts
The NRC Committee emphasizes that weather modification should be
viewed as a fundamental and legitimate element of atmospheric and
environmental science. Owing to the growing demand for fresh water, the
increasing levels of damage and loss of life resulting from severe
weather, the undertaking of operational activities without the guidance
of a careful scientific foundation, and the reality of inadvertent
atmospheric changes, the scientific community now has the opportunity,
challenge, and responsibility to assess the potential efficacy and
value of intentional weather modification technologies.
Thank you for the opportunity to testify. I would be happy to
answer any questions the Subcommittees might have.

Executive Summary

The weather on planet Earth is a vital and sometimes fatal force in
human affairs. Efforts to control or reduce the harmful impacts of
weather go back far in time. In recent decades our ability to observe
and predict various types of meteorological systems has increased
tremendously. Yet during this same period there has been a progressive
decline in weather modification research. Extravagant claims,
unrealistic expectations, and failure to provide scientifically
demonstrable success are among the factors responsible for this
decline. Significantly, every assessment of weather modification dating
from the first National Academies' report in 1964 has found that
scientific proof of the effectiveness of cloud seeding was lacking
(with a few notable exceptions, such as the dispersion of cold fog).
Each assessment also has called for a dedicated research effort
directed at removing or reducing basic scientific uncertainties before
proceeding with the application of weather modification methods. Yet,
this type of intensive, committed effort has not been carried out.
In this, the latest National Academies' assessment of weather
modification, the Committee was charged to provide an updated
assessment of the ability of current and proposed weather modification
capabilities to provide beneficial impacts on water resource management
and weather hazard mitigation. It was asked to examine new
technologies, such as ground-based, in situ, and satellite detection
systems, and fast reacting seeding materials and dispensing methods.
The Committee also was asked to review advances in numerical modeling
on the cloud and mesoscale and consider how improvements in computer
capabilities might be applied to weather modification. This study was
not designed to address policy implications of weather modification;
rather it focused on the research and operational issues. Specifically,
the Committee was asked to:

review the current state of the sciences of weather
modification and the role of weather prediction as it applies
to weather modification, paying particular attention to the
technological and methodological developments of the last
decade;

identify the critical uncertainties limiting advances in
weather modification science and operation;

identify future directions in weather modification research
and operations for improving the management of water resources
and the reduction in severe weather hazards; and

suggest actions to identify the potential impacts of
localized weather modification on large-scale weather and
climate patterns.

Issues and Trends in Weather Modification
Motivation
Increasing demands for water make the potential for enhancing the
sources, storage, and recycling of freshwater a legitimate area of
study. Destruction and loss of life due to severe weather, which is
increasing with population growth and changing demographics, require
that we examine ways to reduce these impacts. In addition, there is
ample evidence that human activities, such as the emission of
industrial air pollution, can alter atmospheric processes on scales
ranging from local precipitation patterns to global climate. These
inadvertent impacts on weather and climate require a concerted research
effort, yet the scientific community has largely failed to take
advantage of the fact that many of the scientific underpinnings of
intentional and unintentional weather modification are the same.

Current Operational and Research Efforts
Operational weather modification programs, which primarily involve
cloud-seeding activities aimed at enhancing precipitation or mitigating
hail fall, exist in more than 24 countries, and there were at least 66
operational programs being conducted in 10 states across the United
States in 2001. No Federal funding currently is supporting any of these
operational activities in the United States. Despite the large number
of operational activities, less than a handful of weather modification
research programs are being conducted worldwide. After reaching a peak
of $20 million per year in the late 1970s, support for weather
modification research in the United States has dropped to less than
$500,000 per year.

The Paradox
Clearly, there is a paradox in these divergent trends: The Federal
Government is not willing to fund research to understand the efficacy
of weather modification technologies, but others are willing to spend
funds to apply these unproven techniques. Central to this paradox is
the failure of past cloud-seeding experiments to provide an adequate
verification of attempts at modifying the weather. A catch-22 ensues in
which the inability to provide acceptable proof damages the credibility
of the entire field, resulting in diminished scientific effort to
address problems whose solutions would almost certainly lead to better
evaluations.

Limitations and Problems
The dilemma in weather modification thus remains. We know that
human activities can affect the weather, and we know that seeding will
cause some changes to a cloud. However, we still are unable to
translate these induced changes into verifiable changes in rainfall,
hail fall, and snowfall on the ground, or to employ methods that
produce credible, repeatable changes in precipitation. Among the
factors that have contributed to an almost uniform failure to verify
seeding effects are such uncertainties as the natural variability of
precipitation, the inability to measure these variables with the
required accuracy or resolution, the detection of a small induced
effect under these conditions, and the need to randomize and replicate
experiments.

Conclusions
The Committee concludes that there still is no convincing
scientific proof of the efficacy of intentional weather modification
efforts. In some instances there are strong indications of induced
changes, but this evidence has not been subjected to tests of
significance and reproducibility. This does not challenge the
scientific basis of weather modification concepts. Rather it is the
absence of adequate understanding of critical atmospheric processes
that, in turn, lead to a failure in producing predictable, detectable,
and verifiable results. Questions such as the transferability of
seeding techniques or whether seeding in one location can reduce
precipitation in other areas can only be addressed through sustained
research of the underlying science combined with carefully crafted
hypotheses and physical and statistical experiments.
Despite the lack of scientific proof, the Committee concludes that
scientific understanding has progressed on many fronts since the last
National Academies' report and that there have been many promising
developments and advances. For instance, there have been substantial
improvements in the ice-nucleating capabilities of new seeding
materials. Recent experiments using hygroscopic seeding particles in
water and ice (mixed-phase) clouds have shown encouraging results, with
precipitation increases attributed to increasing the lifetime of the
rain-producing systems. There are strong suggestions of positive
seeding effects in winter orographic glaciogenic systems (i.e., cloud
systems occurring over mountainous terrain). Satellite imagery has
underlined the role of high concentrations of aerosols in influencing
clouds, rain, and lightning, thus drawing the issues of intentional and
inadvertent weather modification closer together. This and other recent
work has highlighted critical questions about the microphysical
processes leading to precipitation, the transport and dispersion of
seeding material in the cloud volume, the effects of seeding on the
dynamical growth of clouds, and the logistics of translating storm-
scale effects into an area-wide precipitation effect. By isolating
these critical questions, which currently hamper progress in weather
modification, future research efforts can be focused and optimized.
Additional advances in observational, computational, and
statistical technologies have been made over the past two to three
decades that could be applied to weather modification. These include,
respectively, the capabilities to (1) detect and quantify relevant
variables on temporal and spatial scales not previously possible; (2)
acquire, store, and process vast quantities of data; and (3) account
for sources of uncertainty and incorporate complex spatial and temporal
relationships. Computer power has enabled the development of models
that range in scale from a single cloud to the global atmosphere.
Numerical modeling simulations--validated by observations whenever
possible--are useful for testing intentional weather modification and
corresponding larger-scale effects. Few of these tools, however, have
been applied in any collective and concerted fashion to resolve
critical uncertainties in weather modification. These numerous
methodological advances thus have not resulted in greater scientific
understanding of the principles underlying weather modification. This
has not been due to flawed science but to the lack of support for this
particular field of the science over the past few decades. As a result
there still is no conclusive scientific proof of the efficacy of
intentional weather modification, although the probabilities for
seeding-induced alterations are high in some instances. Despite this
lack of scientific proof, operational weather modification programs to
increase rain and snowfall and to suppress hail formation continue
worldwide based on cost versus probabilistic benefit analyses.

Recommendations
Recommendation: Because weather modification could potentially
contribute to alleviating water resource stresses and severe weather
hazards, because weather modification is being attempted regardless of
scientific proof supporting or refuting its efficacy, because
inadvertent atmospheric changes are a reality, and because an entire
suite of new tools and techniques now exist that could be applied to
this issue, the Committee recommends that there be a renewed commitment
to advancing our knowledge of fundamental atmospheric processes that
are central to the issues of intentional and inadvertent weather
modification. The lessons learned from such research are likely to have
implications well beyond issues of weather modification. Sustainable
use of atmospheric water resources and mitigation of the risks posed by
hazardous weather are important goals that deserve to be addressed
through a sustained research effort.
Recommendation: The Committee recommends that a coordinated
national program be developed to conduct a sustained research effort in
the areas of cloud and precipitation microphysics, cloud dynamics,
cloud modeling, and cloud seeding; it should be implemented using a
balanced approach of modeling, laboratory studies, and field
measurements designed to reduce the key uncertainties listed in Box
ES.1. This program should not focus on near-term operational
applications of weather modification; rather it should address
fundamental research questions from these areas that currently impede
progress and understanding of intentional and inadvertent weather
modification. Because a comprehensive set of specific research
questions cannot possibly be listed here, they should be defined by
individual proposals funded by a national program. Nevertheless,
examples of such questions may include the following:

What is the background aerosol concentration in various
places, at different times of the year, and during different
meteorological conditions? To what extent would weather
modification operations be dependent on these background
concentrations?

What is the variability of cloud and cell properties
(including structure, intensity, evolution, and lifetime)
within larger clusters, and how do clouds and cells interact
with larger-scale systems? What are the effects of localized
seeding on the larger systems in which the seeded clouds are
embedded?

How accurate are radar reflectivity measurements in
measuring the differences between accumulated rainfall in
seeded and unseeded clouds? How does seeding affect the drop-
size distribution that determines the relationship between the
measured radar parameter and actual rainfall at the surface?

-----------------------------------------------------------------------
------------------------------------------------
BOX ES.1
Summary of Key Uncertainties
The statements in boldface type are considered to have the highest
priority.
Cloud/precipitation microphysics issues
Background concentration, sizes, and chemical composition of
aerosols that participate in cloud processes

Nucleation processes as they relate to chemical composition,
sizes, and concentrations of hygroscopic aerosol particles

Ice nucleation (primary and secondary)

Evolution of the droplet spectra in clouds and processes
that contribute to spectra broadening and the onset of
coalescence

Relative importance of drizzle in precipitation processes

Cloud dynamics issues
Cloud-to-cloud and mesoscale interactions as they relate to
updraft and downdraft structures and cloud evolution and
lifetimes

Cloud and sub-cloud dynamical interactions as they relate to
precipitation amounts and the size spectrum of hydrometeors

Microphysical, thermodynamical, and dynamical interactions
within clouds

Cloud modeling issues
Combination of the best cloud models with advanced observing
systems in carefully designed field tests and experiments

Extension of existing and development of new cloud-resolving
models explicitly applied to weather modification

Application of short-term predictive models including
precipitation forecasts and data assimilation and adjoint
methodology in treated and untreated situations

Evaluation of predictive models for severe weather events
and establishment of current predictive capabilities including
probabilistic forecasts

Advancement of the capabilities in cloud models to simulate
dispersion trajectories of seeding material

Use of cloud models to examine effects of cloud seeding
outside of seeded areas

Combination of cloud models with statistical analysis to
establish seeding effects

Seeding-related issues
Targeting of seeding agents, diffusion and transport of
seeding material, and spread of seeding effects throughout the
cloud volume

Measurement capabilities and limitations of cell-tracking
software, radar, and technologies to observe seeding effects

Analysis of recent observations with new instruments of high
concentrations of ice crystals

Interactions between different hydrometeors in clouds and
how to best model them

Modeling and prediction of treated and untreated conditions
for simulation

Mechanisms of transferring the storm-scale effect into an
area-wide precipitation effect and tracking possible downwind
changes at the single cell, cloud cluster, and floating target
scales
-----------------------------------------------------------------------
------------------------------------------------

The tasks involved in weather modification research fall within the
mission responsibilities of several government departments and
agencies, and careful coordination of these tasks will be required.
Recommendation: The Committee recommends that this coordinated
research program include:
Capitalizing on new remote and in situ observational tools
to carry out exploratory and confirmatory experiments in a
variety of cloud and storm systems (e.g., Doppler lidars and
airborne radars, microwave radiometers, millimeter-wave and
polarimetric cloud radars, global positioning system (GPS) and
cell-tracking software, the Cloud Particle Imager, the Gerber
Particle Volume Monitor, the Cloud Droplet Spectrometer).
Initial field studies should concentrate on areas that are
amenable to accurate numerical simulation and multiparameter,
three-dimensional observations that allow the testing of
clearly formulated physical hypotheses. Some especially
promising possibilities where substantial further progress may
occur (not listed in any priority) include:

--Hygroscopic seeding to enhance rainfall. The small-scale
experiments and larger-scale coordinated field efforts proposed
by the Mazatlan workshop on hygroscopic seeding (WMO, 2000)
could form a starting point for such efforts. A randomized
seeding program with concurrent physical measurements
(conducted over a period as short as three years) could help
scientists to either confirm or discard the statistical results
of recent experiments.

--Orographic cloud seeding to enhance precipitation. Such a
program could build on existing operational activities in the
mountainous western United States. A randomized program that
includes strong modeling and observational components,
employing advanced computational and observational tools, could
substantially enhance our understanding of seeding effects and
winter orographic precipitation.

--Studies of specific seeding effects. This may include studies
such as those of the initial droplet broadening and subsequent
formation of drizzle and rain associated with hygroscopic
seeding, or of the role of large (>1 mm) particles (e.g., sea
spray) in reducing droplet concentrations in polluted regions
where precipitation is suppressed due to excess concentrations
of small cloud condensation nuclei (CCN).

Improving cloud model treatment of cloud and precipitation
physics. Special focus is needed on modeling CCN, ice nuclei
processes, and the growth, collision, breakup, and coalescence
of water drops and ice particles. Such studies must be based on
cloud physics laboratory measurements, tested and tuned in
model studies, and validated by in situ and ground
observations.

Improving and using current computational and data
assimilation capabilities. Advances are needed to allow rapid
processing of large quantities of data from new observations
and better simulation of moist cloud and precipitation
processes. These models could subsequently be used as planning
and diagnostic tools in future weather modification studies,
and to develop techniques to assist in the evaluation of
seeding effects.

Capitalizing on existing field facilities and developing
partnerships among research groups and select operational
programs. Research in weather modification should take full
advantage of opportunities offered by other field research
programs and by operational weather modification activities.
Modest additional research efforts directed at the types of
research questions mentioned above can be added with minimal
interference to existing programs. A particularly promising
opportunity for such a partnership is the Department of Energy
Atmospheric Radiation Measurement program/Cloud and Radiation
Test bed (DOE ARM/CART) site in the southern Great Plains
(Oklahoma/Kansas) augmented by the National Aeronautics and
Space Administration (NASA) Global Precipitation Mission. This
site provides a concentration of the most advanced observing
systems and an infrastructural base for sustained basic
research. The National Center for Atmospheric Research (NCAR)
and the National Oceanic and Atmospheric Administration's
Environmental Technology Laboratory (NOAA/ETL) also could serve
as important focal points for weather modification research.

In pursuing research related to weather modification explicit,
financial and collegial support should be given to young aspiring
scientists to enable them to contribute to our fundamental store of
knowledge about methods to enhance atmospheric resources and reduce the
impacts of hazardous weather. It must be acknowledged that issues
related to weather modification go well beyond the limits of physical
science. Such issues involve society as a whole, and scientific weather
modification research should be accompanied by parallel social,
political, economic, environmental, and legal studies.
The Committee emphasizes that weather modification should be viewed
as a fundamental and legitimate element of atmospheric and
environmental science. Owing to the growing demand for fresh water, the
increasing levels of damage and loss of life resulting from severe
weather, the undertaking of operational activities without the guidance
of a careful scientific foundation, and the reality of inadvertent
atmospheric changes, the scientific community now has the opportunity,
challenge, and responsibility to assess the potential efficacy and
value of intentional weather modification technologies.
Closing Thoughts
The Academy Committee emphasizes that weather modification should
be viewed as a fundamental and legitimate element of atmospheric and
environmental science. The growing demand for fresh water, the
increasing levels of damage and loss of life resulting from severe
weather, the undertaking of operational activities without the guidance
of a careful scientific foundation, and the reality of inadvertent
atmospheric changes gives the scientific community the opportunity,
challenge, and the responsibility to determine how and to what extent
humans can influence the weather.

Senator DeMint. Thank you, Doctor.
Chairman Hutchison is here. I believe she would like to
make an opening statement.

STATEMENT OF HON. KAY BAILEY HUTCHISON,
U.S. SENATOR FROM TEXAS

Senator Hutchison [presiding]. Thank you.
Well, I very much appreciate the three of you coming. I'm
sorry I'm late, but I do want to talk to you. I've read your
testimony, and I've also read the executive summary of the
report in which you participated. This was an issue brought to
me by a distinguished former State Senator from Texas, John
Leedom, who is with us today, and his wife, Betty, I see. But I
thought that the points that he made to me were certainly worth
pursuing.
And it seems to me, from all of your testimony, that
further research is something that the scientific community
wants to see happen. And I think, from what Dr. Garstang has
just said, that the view of the scientific community and the
committee that you are on is that we shouldn't be running out
there doing things until we have the research that either
proves what the long-term effects are going to be, or not. And
I think it's very important that we pursue this research, which
is why I've introduced the legislation.
I am very interested in the findings and recommendations of
the Committee in which they say that it is recommended that we
have a sustained research effort in this area. And I want to
pursue this a little further when we get into questions. I know
that Senator DeMint has to be on the floor at 3 p.m., so I'm
going to defer to him to ask his questions first. But I am
going to want to talk to the three of you about how we should
pursue this research, which is the purpose of my bill, and to
get the best results, and especially to determine, from what
was said in the report--that there is a growing demand for
fresh water, the increasing levels of damage and loss resulting
from severe weather--would indicate that we should be
researching what we can do to mitigate damage and also provide
a more steady, even, and balanced source of fresh water, rather
than having a Hurricane Katrina while there is a drought in
other parts of our country.
So, I will pursue that, but I will yield to Senator DeMint,
because he has another--this, I will tell you, just so that you
understand--because this is the last week or 10 days of our
session, all of us have hearings and conference committees,
which is what I had to attend earlier, and why I'm late. We had
a conference committee on our transportation bill, and I'm sure
you're going to the floor for your bill. So, why don't you go--
--
Senator DeMint. OK.
Senator Hutchison.--forward, and I will----
Senator DeMint. Thank you----
Senator Hutchison.--follow you.
Senator DeMint.--Chairman.
Just a quick question, and I will have to leave in a just a
moment, but----
This is a fascinating subject for me. The idea that we
could actually impact weather is exciting and, I guess,
frightening, in some ways. But, Dr. Golden, you mentioned just
some successes, the successes of adding to the snowfall in
mountains and, again, I guess we can't get into a lot of
science today, but I assume if we're able to get additional
snow in one area, that some other area is not going to get as
much rainfall or moisture-fall. I mean, we're not putting more
moisture in the air, we're just collecting it in a different
place. Is that the concept?
Dr. Golden. This is one of the very areas that we need to
do a lot of additional research under Senator Hutchison's bill.
But the work that has been done--and there are--we did some of
this on our FACE program in Florida. We looked at what you're
talking about is extra-area effects. If you seed in a target
area, are you robbing Peter to pay Paul in areas that are
downwind? And both in the FACE Project, as well as in other
States--in Utah, we looked at possible downwind effects from
seeding in the mountains of Utah. Did they see any decreased
snowfall in Southwestern Wyoming? The answer is no. Even the
most ardent proponents of the mountain seeding will tell you
that you're only processing--you're only affecting a very small
fraction of the water vapor that passes over the mountains. And
so, all of the results in both winter oragraphic mountain
seeding, as well as convective storm seeding suggests that
either you have no effect downwind or it's a slight increase.
But, again, there needs to be additional research. There's
nothing that suggests large increases outside your target area.
It's either no effect or very weak positive effect.
Senator DeMint. And you mentioned other countries
apparently using this successfully. I mean, are there any
studies that the scientific community would recognize that says
Australia, or, I think you mentioned, China, have actually been
successful in weather modification?
Dr. Golden. Some of them, yes, but it's still--I think what
Dr. Garstang says is true, there still needs to be work on
evaluation. And while I'm not a strong proponent of using only
statistical evaluation, I think, for example, there are--some
of the new computer models and tracers--we now have come a long
way in just the last 10 years; and this is an effort that we
pioneered in this country. There are now tracer techniques that
you can use right when you seed to tell you not only how much
increase in snow is due to the seeding, but how much of the
seeding material actually made it into the snow that fell. And
so, this has just been developed over the last 10 years, and
they're just starting to apply this technology in the Australia
program. So----
Senator DeMint. Well, thank----
Senator Hutchison. Could I ask a question just on that----
Senator DeMint. Sure.
Senator Hutchison.--same subject, while you're here?
There are ten States and probably 66 operational
modification programs just ongoing now by States and local
water agencies. Is there any place that those projects that are
ongoing, operations that are ongoing, where data is collected
at a central point so that we do see the effects of those
particular operations as they are supposed to be working?
Dr. Golden. No. You raise a very good point. I mean, that's
what we're all about today, is--I talked to one of the biggest
operators that supports many of these programs, both in the
U.S.--many of the operational weather modification programs--
and they told me that--he estimates that there is now an
expenditure per year, a combined expenditure, just in our
country, of $25 to $30 million per year on operations. But
since the demise of my AMP program, there is no central focus.
And, frankly, most of the operational groups that support the
seeding activity feel that most of their funding has to go to
the seeding effort, to the operations. So, they look to the
Government. They look to the Federal Government to play the
major role here.
To be honest with you, some of them, recognizing the value
of research to helping them evaluate what they do, are
supporting small research efforts. The newest entry into this,
by the way, is the State of Wyoming. They're about to start a
new $8 million program of snowpack seeding enhancement.
Senator Hutchison. At the very least, we ought to be----
Senator DeMint. Yes.
Senator Hutchison.--gathering the data.
Senator DeMint. So, we're spending $25 million a year, but
we really don't have any quantitative data that suggests that
it works, just more of an--empirical evidence that people
believe there is some impact, right?
Dr. Golden. They do their own evaluation. No, I don't mean
to say--they are not--not much of that money is going to
support any of the research that Dr. Garstang recommended in
his report. Most of that is for their operations and some
evaluation.
Senator Hutchison. But nothing is gathered nationally----
Dr. Golden. Right.
Senator Hutchison.--to see what the effects are.
Senator DeMint. You're going to have to excuse me.
Senator Hutchison. OK, thank you.
I wanted to ask you, because we've been through some
particularly bad weather situations this year, is there any
thought in the scientific community that you could, by, say,
seeding, maybe, a hurricane in the early stages, that you could
lessen its effect, make it start dropping earlier, and lessen
its effect when it hits land? Is there any potential for that
kind of modification? We've been talking about modification,
obviously, over land, where you're trying to get rain for
crops. But we also are looking at ways to maybe even out the
kind of weather and rainfall that we would have. Is there any
hope that we could eventually use some kind of scientific means
like this to take out the violence of a storm?
Dr. Garstang. I'll pick that one up, Senator Hutchison.
Yes, as Dr. Golden said, there was a program, STORMFURY,
that did, indeed, attempt to--and they used the word
``moderate'' a hurricane, change its wind speeds. And although
it's controversial now, there was a conclusion that they had,
indeed, got evidence for a reduction of 15 percent in the wind
speeds. Now, if you take a hurricane wind from 100 miles an
hour down to 85 miles an hour, the damage is the square of the
wind velocity, so you mitigate damage considerably. However, as
I said, there's question about that.
There are no current methodologies that could be employed
to reduce or to deflect a hurricane. However, there are very
promising computer models that are beginning to suggest how we
might approach this. And, interestingly enough from what Dr.
Golden said, one of the most advanced pieces of work is being
done by the European community's National Center for
Meteorology or long-range/medium-range forecasting. And it's
using our ideas. But there are efforts in this country where
the model suggests that very small effects might have quite
drastic consequences. And this is a characteristic of the
atmosphere.
I'm sure you know that the whole theory of chaos came from
a meteorologist, Dr. Ed Lorenz, from MIT, where he was trying
to determine what, in all these small effects--and to use the
kind of analogy that he used, the flapping of a butterfly's
wings in Brazil creates a tornado in Kansas. In other words,
these very tiny effects can have, ultimately, very large
consequences.
Models now are being used to find these. Are they there,
and can we find them? And Dr. Ross Hoffman's work suggests
that, yes, they are. It's not clear how you would necessarily
bring that about, but if we don't pursue this work, we will
never know the answer.
So, the answer is: not right now, but yes in the future.
Senator Hutchison. Thank you.
Dr. DeFelice?
Dr. DeFelice. Yes, I'd like to just add to this. I think
the--excuse me, technical difficulties--I think under your
bill, once it's passed, I would recommend to the board an
implementation plan for the research that would be conducted
under it, and part of that plan would involve hurricane
modification and some of the issues that my distinguished
colleagues have mentioned. But I would just want to emphasize
the need to do modeling studies to test all possible seeding
scenarios relative to the result of those inputs. Get the best
models that we can on hurricanes, because there are really--
there's some really good ones out there, even in the United
States. And then have some of our computer scientists add a
computer program--or a subroutine that would act like we were
seeding them, but not do any seeding.
Under our plan, the implementation plan for this bill,
there would be no way that the Government would be doing any
operational cloud-seeding or anything like that. They would--
hurricane modification and all that research would have to be
done by models. And once the modeling studies were complete,
then one might form a hypothesis which might be testable out in
the field. But we would know what would happen or think we know
what would happen, based on the models. I just wanted to
emphasize the use of models in any severe-storm type of
modification research that happens under this bill. At least
that would be my view and hope.
Senator Hutchison. If you were going to do an
implementation plan--say, we pass the bill, we have
appointments to the board, and you would want a representative
board from the different areas of weather expertise, but what
areas do you think would be the most productive in which to do
research? Obviously, cloud-seeding for fresh water. And
hurricane or violent weather modification would be two. What
else could we gain from this kind of effort?
Dr. DeFelice. I'll start, and then I'm sure there'll be
plenty to add to it.
I would think that we might consider looking into clearing
out fog in the vicinity of airports, and perhaps other areas,
particularly in the Northeast, which might benefit from
increased sunlight particularly during the winter. So, these
would be cold clouds. Another area would be hygroscopic
seeding. And there's a lot that's not known about that. There's
a lot of promising results.
Senator Hutchison. ``Hygroscopic,'' being?
Dr. DeFelice. Putting small salt nuclei into the proper
part of the cloud so that those nuclei would help enhance the
interaction between the droplets in the cloud, so that would
then, in turn, produce more precipitation.
Senator Hutchison. Is that different from other types of
cloud-seeding, or are there different forms?
Dr. DeFelice. It's just that--that is different in the
sense that it's just a different way to trigger the
precipitation process in the cloud. You can use agents that
would grow ice crystals in the cloud. But those clouds would
have to be cold enough for the ice to exist, if it was to form.
Senator Hutchison. OK.
Dr. DeFelice. But those would be the primary areas.
Senator Hutchison. Any others?
Dr. Golden. I want to emphasize--and I wish Senator DeMint
were here--that one of the terrible things that happened when
we cut STORMFURY in the early 1980s was that, beginning at that
point, the research funding for hurricane research in NOAA
steadily declined. And it's declined ever since. The other
thing that happened is that most of our research on cloud
physics evaporated. People left the agency, people changed
their careers. In fact, there are almost no cloud physicists
left--cloud physicists in NOAA have become an endangered
species.
Why is that important? It means that if you don't
understand the cloud physics, as Dr. Garstang emphasized, you
have no hope of understanding how you might beneficially modify
clouds to produce increased rainfall. And that feeds back into
being able to predict heavy rain and heavy snow. In other
words, this is one of the top priorities for my colleagues in
the National Weather Service. I mean, we all get frustrated
that our skill scores, our forecast accuracies for heavy rain
or heavy snow aren't what they need to be. And so, this is all
linked together, so that there is no doubt in my mind that any
investment by this bill in weather modification research will
yield big payoffs in the prediction arena. And, as I said in my
testimony, ultimately we're never going to be able to convince
ourselves or anyone else that we're successful in weather
modification unless we can do a good job of predicting the
unmodified natural event. That's the--that's one of the most
fundamental questions.
Dr. Garstang. I certainly agree with all of those
sentiments. But I'd like to emphasize that if the bill could
bring cohesive and sustained effort directed at solving the
outstanding problems that we know are roadblocks to our
progress, if you can remove these roadblocks, you can progress.
And if you simultaneously, with this coherent program, brought
to bear on it all of the technological advances that have
occurred in the last 30 years, there would be immediate and
tremendous advances. Dr. Golden has referred to a couple.
For example, in the successful, I think, attempts at
increasing snowpack on the Sierras and western slopes of the
Rockies, we didn't know where the seeding material was going.
We now can determine precisely where it's going. And often it
didn't go where we thought it was going, didn't go where it
would do any good. We also can precisely describe the flow
fields through the cloud. We couldn't do that 10 years ago.
These techniques have not been coherently brought to bear
on weather modification. As soon as we do that, we will have
immediate results.
Let me give you an analogy. Let's assume that all of
cardiac investigations were prevented from using the
technological advances that have occurred in heart research
over the last 20 years. Where would we be in preventing heart
disease today? We would be way behind where we are.
We have not brought these same kind of sophisticated
techniques, which are in place, to bear on the problem. And if
you could create that situation where that was possible, you
would get immediate results.
Senator Hutchison. Have you looked at my bill? I would like
to ask each of you. And do you have any suggestions on any ways
to improve it?
Basically, what I'm trying to do is establish this research
and a board that would be made up of experts from these various
areas with various expertise that would be advisory to the
Department of Commerce and NOAA. And my question is, Is there
something that you would suggest that would make it any more
able to achieve the goal of more emphasis on research, an
implementation of the research, and an advisory board made up
of experts that would really focus the Department on the areas
that should be looked at that we've discussed?
Dr. DeFelice. I think, as--let me just check--thank you. As
I looked through the bill, I think one rule of thumb that I'd
like to see--and I believe I've seen this--was to have a
multidisciplinary approach to the research agenda, and have the
board basically get together with these multidisciplinary
components of the field and discuss the priorities. Now, we
come up with priorities, and this is great. And, from what I
heard they make sense. But there might not be enough money to
carry out all of those particular items. So, I think we need to
make sure that we have representatives from all components of
the system that we're trying to research, including the general
public. So, if the general public is going to be involved, then
we might have to have an outreach component, which I strongly
urge be in there. I think it is. And we would want
representatives from the scientists--science community, maybe
some sociologists, economics-type people, commerce, and, so on.
But the point is, we want people that are affected by the
system, and we need those people to represent each component of
that system, so that when we do develop the priorities,
everybody will be represented in that process, and will be part
of it, and will--should stay with that process from beginning
to end.
Senator Hutchison. Well, I'd--we certainly----
Dr. DeFelice.--that's great.
Senator Hutchison.--do have a multidisciplinary concept,
and if there are any other disciplines that should be added, I
would like for you to write me a letter about that later.
Yes?
Dr. Golden. No, I don't want to tinker with your bill. I
think that the board is well represented. Is NSF--do they have
a representation on the board?
Senator Hutchison. It is the--one representative of the
National Center for Atmospheric Research of the National
Science Foundation.
Dr. Golden. OK. Because they, in the past--this is no
longer the case, but in the past, I know that during my AMP
Program, we did--some of the States actually got--funded
proposals through NSF, and then NSF has also stopped supporting
weather modification research. But, I mean, your bill--I think
it's fine. I think it says that the board can appoint extra
staff, and it can appoint subcommittees. And, no, I wouldn't
want to second-guess that. I think once they're assembled, then
they can start tackling this issue of national priorities, and
I think they'll come to the AMS, they'll come to the American
Society of Civil Engineers, they'll come, hopefully, to the
Weather Modification Association, and--I mean, these are the
venues where the national priorities could be set. I have no
problem with that.
Senator Hutchison. Dr. Garstang?
Dr. Garstang. I have only had the benefit to discuss your
bill. I have not read it. We hadn't--it wasn't in time when I
got notified to appear here. But I would be glad to look at it
carefully, because I gather, from both yourself and from
discussions, that you've incorporated a lot of ideas, results
from the NRC report. And I would be glad to send these to you--
to your staff in writing right away.
Senator Hutchison. I would really be pleased if you would,
because I think we all are on the same wavelength regarding the
need to have an emphasis here, trying to implement that through
an advisory board. I think the advisory board--we tried to make
it representative of the different areas of expertise, and--so,
I'd like to move the bill, so I'd like to have all of your
comments and look forward to perhaps being able to do this in--
--
OK, I'm told that Senator Ben Nelson had a witness
recommendation who was unable to attend the hearing and has
submitted a statement to be included in the record, Commander
Donald Wilhite, Director of the National Drought Mitigation
Center at the University of Nebraska. *
---------------------------------------------------------------------------
* The information referred to has been printed in the Appendix.
---------------------------------------------------------------------------
Senator Hutchison. OK. Well, I have no further questions.
Is there anything further that any of you would like to add for
the record?
[No response.]
Senator Hutchison. If not, we will give you a copy of the
bill, Dr. Garstang. And I hope that we can all come together.
And I hope Senator DeMint will work with us, as well, to try to
move this forward.
Thank you very much for your time, and I learned a lot, and
I think we can make some great headway in this area with your
expertise.
Thank you.
[Whereupon, at 3:25 p.m., the hearing was adjourned.]

A P P E N D I X

Prepared Statement of Hon. E. Benjamin Nelson,
U.S. Senator from Nebraska

Due to the short notice of the scheduling of the Joint Subcommittee
hearing on S. 517, ``The Weather Modification Research and Technology
Transfer Authorization Act of 2005,'' I am unable to attend the hearing
today. This is an important issue and I regret not being able to
reschedule prior commitments in order to be there.
However, I did want to take the opportunity, as we discuss weather
modification, to highlight an area of research that is happening at the
University of Nebraska related to drought mitigation. While the focus
of this hearing is weather modification, I believe it is relevant to
address another aspect important to this area of research, which is
adequate monitoring of weather patterns so that we may appropriately
respond to and mitigate the effects of adverse weather.
The National Drought Mitigation Center (NDMC), located at the
University of Nebraska-Lincoln, was established in 1995 and performs a
number of activities of importance to Nebraska, the region, and the
Nation. Its functions include maintaining a web-based information
clearinghouse, drought monitoring, the preparation of the weekly U.S.
Drought Monitor (which covers all 50 states), the development of
drought policy and planning techniques, collaborative research on
improved decision tools for agricultural producers and natural resource
managers, and outreach and training workshops for Federal, State, and
foreign governments and organizations.
The NDMC has worked with most states in the development of drought
mitigation and response plans aimed at reducing vulnerability to
episodes of severe drought. The NDMC has worked closely with the
Western Governors' Association and NOAA in formulating the proposal for
a National Integrated Drought Information System. This system is
currently being implemented by NOAA with the assistance of the NDMC.
With this statement, I am submitting a statement from Dr. Donald
Wilhite, Director of the NDMC, which details more fully the work they
are doing at the University of Nebraska. I believe the research that is
being conducted there is critical to our ability to respond to the
devastating effects of drought.
This research is especially relevant to Nebraska and other Plains
states right now, which have been experiencing drought conditions for
several years; but the research done by the NDMC has a national
benefit. Droughts have plagued all regions of the country over the past
10 years and many parts of the West have been in drought for 5 to 7
years. They are often slow in developing, but the costs and indirect
effects have a substantial impact on water supplies, agriculture,
energy production, natural resources, recreation and tourism,
transportation, development, and the environment.
The effect of drought in recent years in my state has been
devastating. Its impact has been felt throughout the economy of
Nebraska. While drought typically does not produce dramatic news
footage like a hurricane or tornado will, it is nonetheless, a
disaster.
I believe it is crucial to encourage more investment in research in
programs such as the NDMC. The research done upfront in monitoring
drought trends will help our capabilities to mitigate and respond to
its effects in a much more effective manner. I am hopeful that we can
hold a hearing on drought in the Disaster Prevention and Prediction
Subcommittee next year. This is an important issue that I believe
warrants more discussion.

______

Prepared Statement of Dr. Donald Wilhite, Director, National Drought
Mitigation Center, University of Nebraska-Lincoln

I appreciate the opportunity to submit this statement on behalf of
the National Drought Mitigation Center (NDMC), which is located at the
University of Nebraska in Lincoln. Climate variability is an important
issue that affects everyone across the United States. This is true
whether it is related to heating bills for the upcoming winter; to El
Nino or La Nina events that might cause flooding or drought; or the
frequency of natural hazards striking our Nation, like the numerous
hurricanes during the past two years. The truth is that drought is one
of the costliest hazards to affect the country: FEMA has estimated that
the annual losses due to drought are approximately $8 billion, which is
a higher estimate than for any other natural hazard. Hurricanes
Katrina, Rita, and Wilma may change that placement slightly, but
drought remains a serious threat across the United States. The impacts
resulting from drought are complex, and as our vulnerability to
droughts changes with the shifting pressures on the Nation's finite
water resources, impacts due to drought may increase in the future.
I would like to emphasize that drought is a normal part of the
climate across the United States. At any given time, approximately 14
percent of the Nation is in severe drought or worse. It is also
important to note that multiple-year events (like the 1930s and 1950s,
and the 1960s along the East Coast) are not unusual events in the
paleo-climate record. For this reason, we need to be prepared for
droughts, and focus our attention on mitigation and planning strategies
that would reduce drought impacts before droughts strike.
The National Drought Mitigation Center (NDMC) was formed in 1995.
At that time, there was no national initiative or program that focused
on drought monitoring, mitigation, and preparedness and the Nation was
just coming out of a period of serious drought lasting from 1988 to
1994. I have been involved in drought-related research and outreach
since 1980, and the formation of the NDMC developed out of a national
conference on drought that I organized in 1994. During the first year,
our funding came from both NOAA and USDA. Since then, the NDMC's base
operating budget is provided through USDA and supplemented by numerous
grants from NOAA, NSF, NASA, USGS, BoR, and other USDA agencies.
The NDMC's program is directed at lessening societal vulnerability
to drought through a risk-based management approach. The NDMC's
activities include promoting and conducting research and outreach
activities on drought monitoring, mitigation, and preparedness
technologies; improving coordination of drought-related activities and
actions within and between levels of government; and assisting in the
development, dissemination, and implementation of appropriate
mitigation and preparedness technologies in the public and private
sectors. Emphasis is placed on research and outreach projects and
mitigation/management strategies and programs that stress risk
management measures rather than reactive, crisis management actions.
After the NDMC formed, a severe drought struck the Southern Plains
and Southwestern United States in 1995-96. Beginning in 1999, the
Nation has experienced another series of drought events. These droughts
peaked in 2000 and 2002, when close to 40 percent of the Nation was
considered to be in severe drought or worse. At the end of July 2002,
all 50 states were experiencing some level of dryness or drought,
according to the U.S. Drought Monitor. For states in the West (Montana,
Wyoming, Nebraska, New Mexico, and Colorado), the drought became a
multiple-year event that continues in some of these locations. For
states in the Southeast (Georgia and South Carolina, for example), an
unprecedented five-year drought took place between 1998 and 2002.
Even during 2005, when the percent area of the country experiencing
serious drought fell below that of previous years, an extreme drought
spread over parts of Illinois, Iowa, Missouri, Arkansas, and Texas. For
some locations, the summer was one of the driest ever. At a few other
locations, 2005 is on pace to be the driest year on record, surpassing
even the dryness experienced during the famous drought years of the
1930s and 1950s. The area in drought in 2005 included a portion of the
Nation's Corn Belt. Estimates of crop losses for Illinois originally
totaled $1.3 billion, but recent estimates have improved that number to
approximately $0.7 billion, mainly in the northern and central parts of
the state. These drought losses could have been much worse without the
well-timed moisture remnants moving across the area as a result of
several of the hurricanes that struck the Gulf Coast in 2005. The last
big drought to hit the Corn Belt hard was in 1988, with estimated crop
production-related losses of approximately $15 billion. We narrowly
dodged a huge bullet in 2005.
Through these recent droughts, the NDMC has continued to work
across the country on its mission. The NDMC maintains its involvement
in drought monitoring through the U.S. Drought Monitor map, which is a
weekly assessment of the current drought conditions. Two of the NDMC
staff, Mark Svoboda and Michael Hayes, serve as authors for this
product, along with partners at NOAA and USDA. The NDMC also
participates in the monthly North American Drought Monitor, which
includes collaboration with Canadian and Mexican scientists. Several
countries and regions around the world have expressed interest in
adopting the Drought Monitor format to assess drought conditions. The
NDMC has been involved in a NATO project with the Czech Republic to
investigate drought monitoring opportunities in Central Europe. In
November 2005, the NDMC, NOAA, and USDA will be participating in a
bilateral workshop with the Chinese Meteorological Agency on drought
monitoring strategies for China.
The NDMC is continuing to conduct research in the broadly defined
areas of drought monitoring, mitigation, and planning. We continue to
work with NOAA and the Western Governors' Association on the
implementation of the National Integrated Drought Information System
(NIDIS). The NDMC recently launched a new web-based product directed at
development of a web-based drought impacts tool to help NOAA, USDA, and
other agencies determine the impacts associated with drought in a
timely manner. The NDMC has a proposal pending with NOAA to further
support this activity.
In terms of outreach, education, and training, the NDMC continues
to maintain and improve its website (drought.unl.edu) and the U.S.
Drought Monitor website. These two sites resulted in more than 12
million hits in 2005. We organized and conducted three drought
workshops during 2005 and participated in many other workshops and
conferences throughout the United States and internationally. The
Center continues to assist other states and local governments in the
development or revision of drought plans. Thirty-eight states now have
drought response or mitigation plans in place, largely through the
efforts of the NDMC.
In summary, the NDMC strongly supports more research and
development to investigate issues of climate variability, natural
hazards, and drought. Our experience with drought is that, in the long
run, by making a wise initial investment, the Nation will save money by
improving our capability for drought monitoring, mitigation, and
response. Initial investments like these will reduce the adverse
affects of future climate events on our Nation.
______

Executive Office of the President, Office of Science and
Technology Policy
Washington, DC, December 13, 2005
Hon. Kay Bailey Hutchison,
Chairman,
Senate Subcommittee on Science and Space,
Commerce, Science, and Transportation Committee,
Washington, DC.

Dear Senator Hutchison:

This letter is in response to S. 517, ``the Weather Modification
Research and Development Policy Authorization Act of 2005,'' reported
out by the Senate Committee on Commerce, Science and Transportation on
November 17, 2005 (Senate Report No. 109-202). While the Administration
recognizes the Committee's interest in weather modification research
and development, there is a host of issues--including liability,
foreign policy, and national security concerns--that arose in the past
and should be adequately considered before the U.S. Government
undertakes the coordinated national research program this legislation
would require.
The Administration respectfully requests that you defer further
consideration of the bill pending the outcome of an inter-agency
discussion of these issues that the Office of Science and Technology
Policy (OSTP) would coordinate--with the Department of Justice on legal
issues, with the Department of State on foreign policy implications,
with the Departments of Defense and State on national security
implications, and with pertinent research agencies to consider the
reasons the U.S. Government previously halted its work in this area. At
the conclusion of this review, the Administration would report back to
you on the results of these discussions so you are fully apprised of
all possible issues associated with authorizing a new Federal program
on this topic.
Specifically, the Administration believes concerns in the following
areas must be better understood:

Local Political & Legal Ramifications

--Because small scale weather modification (e.g., cloud
seeding) may promote rain in one area to the detriment of
another, weather modification could result in inter-state
(including Indian Tribes) litigation or private citizen
litigation against the modification programs.

--The legal and liability issues pertaining to weather
modification, and the potential adverse consequences on life,
property, and water resource availability resulting from
weather modification activities, must be considered fully
before the U.S. Government could take responsibility for this
new research program.

International and Foreign Policy Implications

--Small and large scale (e.g., hurricane) weather modification
efforts could benefit the United States to the detriment of
other countries (such as Canada or Mexico).

--Given global weather patterns, whether one country ``owns''
its weather so as to assert intra-border control with extra-
border consequences, must be considered under present
international conventions.

--The manner in which such a program could benefit or harm the
present U.S. positions on foreign policy matters, such as
global warming/climate change, should also be considered.

National Security Implications

--The U.S. Government's previous weather modification programs
were part of our Cold War history; restarting them today could
promote (possibly hostile) foreign responses.

--In 1978, the United States became a party to an international
treaty banning the use of weather modification for hostile
purposes. While modification for peaceful purposes is allowed,
whether well-intentioned programs could be considered
``hostile'' and perceived to violate this ban should be
considered.

Research Issues

--The Department of Commerce's National Oceanic and Atmospheric
Administration's (NOAA) primary atmospheric and meteorological
research focus is on improving weather forecasting, which has
proven to save lives and property. NOAA abandoned weather
modification activities some time ago in favor of other
research areas that more directly relate to the agency's core
mission and responsibilities.

--Redirecting funding to focus on weather modification can
shift funds away from other important programs such as research
to improve weather forecasting capabilities for severe weather
events and research to better understand climate variability
and change.

In addition to discussing these concerns on an interagency basis,
and in recognition of your interest in this area, OSTP would be willing
to charter a study to address the above issues. This study would be
conducted by the Science and Technology Policy Institute (STPI), a
federally-chartered research and development center that provides
objective, technical advice to OSTP. The study would address the
history and current status of weather modification research. Such a
study will help us understand the technical position of this field of
science, the significance of the issues discussed above, and the
field's historical context.
The Administration requests that you not move forward with your
legislative proposal until a better understanding can be developed of
the full range of possible implications.
Thank you for your consideration.
Sincerely,
John H. Marburger, III,
Director.
______

Response to Written Questions Submitted by Hon. Daniel K. Inouye to
Dr. Joseph H. Golden
Weather Board
Question 1. What is this Board's legal and line of authority
relationship to the Secretary of Commerce and the Administrator of
NOAA?
Answer. There is no legal and line of authority relationship of the
Board to the Secretary of Commerce and NOAA. However, a Subcommittee
would be established under OSTP and a board of private advisors will
support the Subcommittee's efforts. NOAA will be a Co-Chair of the
Subcommittee with NSF.

Question 2. What is the legal and scientific basis for creating
such a powerful entity?
Answer. This entity is being established to study the effectiveness
of a weather modification program and would not establish direct
authority to conduct operational weather modification.

Question 3. The establishment of this Board appears to place
weather modification research above all other types of atmospheric
research as a priority for funding within the Federal system. Why?
Answer. No, I do not believe the bill places weather modification
research above any other type of atmospheric research within the
Federal agencies. Further, one cannot divorce weather modification
research from basic atmospheric research. One must not forget that a
prerequisite for meaningful weather modification is that one must first
understand the phenomenon being modified. Thus, weather modification
research always adds to the body of knowledge of basic weather we
already have now, resulting in better forecasts and warnings of most
weather phenomena. I strongly believe that now is the time to begin a
sustained Federal effort in weather modification research, not only to
determine optimum conditions and appropriate technologies for winter
snowpack and summer rainfall enhancement, but for studies of severe
storm modification (including hurricanes and tornadoes) as well. I have
no doubt that some of the most urgent weather modification research
will directly benefit NWS/NOAA goals as well in short-term weather
forecasts and warnings.

Question 4. Would this board have subpoena powers and the power to
issue ``rules,'' as is suggested by the bill?
Answer. No, I don't anticipate that the Board, in either bill,
would have subpoena powers. Nor do I feel that it should issue
``rules,'' as other groups like the ASCE already issue best-practice
documents for weather modification operations. The Board should
organize and coordinate a national Federal program in weather
modification research and technology development, and recommend needed
funding to accomplish these tasks (through the expert Subcommittee).

Question 5. Is the purpose of the Board to essentially create an
independent agency dedicated to the promotion of weather modification
research and distribution of grants? Please explain.
Answer. No, again, the Board and its Subcommittee of experts should
develop a coordinated national program of research through existing
Federal agencies, including especially NOAA, NSF, and NASA.

______

Response to Written Questions Submitted by Hon. E. Benjamin Nelson to
Dr. Joseph H. Golden

Legal Issues of Weather Modification
Has anyone considered the legal issues involved in weather
modification? There is only a certain amount of moisture in the
atmosphere; if artificial measures are used to make it rain in a
particular location to relieve drought, for example, that water is
diverted from another location where it would have ultimately fallen.
This raises similar issues as water rights controversies, where rivers
have been diverted to accommodate certain interests at the expense of
others.
Question 1. Has the scientific community considered the legal
implications of weather modification?
Answer. Yes, the scientific community has carefully considered the
legal implications of weather modification for many years. One of my
esteemed colleagues in the weather modification community (deceased)
was Ray Jay Davis, a lawyer from Salt Lake City. My colleague, Dr. Tom
DeFelice will include more details and some of Mr. Davis' writings on
legal issues in his response to your question.

Question 1a. Shouldn't Congress be concerned that any government
supported Weather Modification Board might support research and
development of weather modifications without considering the legal
implications?
Answer. I believe that the Board will be composed of a broad cross-
section of public and private individuals who will act responsibly,
with additional oversight by OSTP. Legal implications become most
important in weather modification operations, but at this time, no
operational seeding will be conducted by the Federal Government in any
research supported by the bill. The Congress passed a Public Law in
l971 that requires all operational weather modification projects in the
U.S. to report details of their projects at least once a year to NOAA.

Question 2. Have you addressed the basic question of who owns the
weather?
Answer. There is no sole ownership of the weather, therefore, any
large-scale operational weather modification projects have always had
to address both legal and environmental issues. For example, the NOAA/
Navy joint hurricane modification Project STORMFURY had to produce an
extensive study of possible environmental impacts prior to its
commencement, and these were all documented in an EIS Report subjected
to peer review. Currently, the Weather Modification Association
certifies weather modification operators, and includes ethical and
legal guidelines in the process.
Funding
I am concerned that there are a number of areas within weather
research that are inadequately funded. For example, drought is of
particular concern to my state right now. The National Drought
Mitigation Center (NDMC) in Nebraska has only been in existence since
1995. Previously, no national initiative or program existed to monitor
drought trends. The work at the NDMC in monitoring drought, not only in
Nebraska, but nationwide, will help us mitigate and respond to its
effects in a much more effective manner. This is only one of numerous
programs addressing weather monitoring, mitigation, and response that
is years behind where it could be.
Question 1. Should funding of new research on weather modification
be a greater priority than research in the weather we already have now?
Answer. No, I do not believe either version of the bill places
weather modification research above any other type of atmospheric
research within the Federal agencies. One cannot divorce weather
modification research from basic atmospheric research. One must not
forget that a prerequisite for meaningful weather modification is that
one must first understand the phenomenon being modified. Thus, weather
modification research always adds to the body of knowledge of basic
weather we already have now, resulting in better forecasts and warnings
of most weather phenomenon. I strongly believe that now is the time to
begin a sustained Federal effort in weather modification research, not
only to determine optimum conditions and appropriate technologies for
winter snowpack and summer rainfall enhancement, but for studies of
severe storm modification (including hurricanes and tornadoes) as well.
I have no doubt that some of the most urgent weather modification
research will directly benefit NWS/NOAA goals as well in short-term
weather forecasts and warnings.

Question 2. Shouldn't we ensure that existing research is
adequately funded in order to protect commercial and governmental
interests before making a commitment to support private research?
Answer. Yes, we should ensure adequate funding for Federal weather
research. This bill will not make a commitment to direct private
research in weather.
______

Response to Written Questions Submitted by Hon. Bill Nelson to
Dr. Joseph H. Golden

Funding
The Hurricane Research Division of NOAA's Office of Atmospheric
Research has been inadequately funded for many years. As a result,
research staff vacancies have gone unfilled, years of data have gone
unanalyzed, and the science of hurricane prediction--especially with
regard to intensity--is years behind where it could be.
Question 1. Should funding of new research on weather modification
be a greater priority than research in the weather we already have now?
Answer. No, I believe that the two types of research are both
needed and are not mutually exclusive. Weather modification research
will certainly add to the body of knowledge of the weather we already
have now. This research will be supportive and complementary. Many of
the most critical research issues for weather modification involve
technology and scientific questions that directly impact the short-term
weather forecast and warning problems faced by my colleagues in the
National Weather Service and the U.S. Military.

Question 2. Shouldn't we ensure that government hurricane research
is adequately funded in order to protect lives before we make a
commitment to support private research in weather research that has
primarily only commercial applications?
Answer. Yes, we should ensure adequate funding for government
research. I am knowledgeable about the need for hurricane research.
This bill would not make a commitment to support private research in
weather.
I believe that the premise of this question is incorrect, because
the bulk of the research and funding to carry it forward would occur in
the Federal weather labs and the universities. The weather modification
research would have applications extending far beyond ``commercial
applications.'' The outputs of this research would also have immediate
payoffs to helping Federal agencies reach their GPRA goals in improved
observations, modeling and improved forecast/warning performance for
NWS. For example, improved 3-D models for determining transport of
seeding materials into cloud systems could also be used for tracking
bioterrorism releases in populated areas and for improved forecasts of
air quality.
______

Response to Written Questions Submitted by Hon. Daniel K. Inouye to
Dr. Thomas P. DeFelice

Weather Board
Question 1. What is this board's legal and line of authority
relationship to the Secretary of Commerce and the Administrator of
NOAA?
Answer. Recent bill mark up discussions call for a permanent
subcommittee (Weather Modification) within the Office of Science and
Technology, who's chair would report directly to the President's
Science Advisor.

Question 2. What is the legal and scientific basis for creating
such a powerful entity?
Answer. There are multiple reasons to take everyday basic and
applied science knowledge, combine it with latest technologies and
apply them creating not only improved science and technology, but also
tools that better serve and support the people. There is no funding to
accomplish said, and time is running out. This subcommittee is
necessary to study and verify the effectiveness and reliability of the
science of weather modification.

Question 3. The establishment of this board appears to place
weather modification research above all other types of atmospheric
research as a priority for funding within the Federal system. Why?
Answer. No, the establishment of this board does not place weather
modification research above all other types of research, Research
related to weather modification more visibly serves societal needs
(such as providing more water for reservoirs, energy generation or more
sunshine for mental wellbeing, energy storage, reducing the destructive
forces associated with hurricanes, or drought mitigation), and also
provides data for the research already underway.

Question 4. Would this board have subpoena powers and the power to
issue ``rules,'' as is suggested by the bill?
Answer. No, the Board will only report to the Subcommittee which
will be comprised of Federal agencies.

Question 5. Is the purpose of the Board to essentially create an
independent agency dedicated to the promotion of weather modification
research and distribution of grants? Please explain.
Answer. No, the Board will report suggestions and provide answers
to technical questions issued by the subcommittee.
______

Response to Written Questions Submitted by Hon. E. Benjamin Nelson to
Dr. Thomas P. DeFelice

Question 1. Has anyone considered the legal issues involved in
weather modification? There is only a certain amount of moisture in the
atmosphere; if artificial measures are used to make it rain in a
particular location to relieve drought, for example, that water is
diverted from another location where it would have ultimately fallen.
Answer. Yes there is a certain amount of moisture in the atmosphere
and most of it naturally stays there in some form or another. Very
little atmospheric moisture falls out as precip (rain) on a global
average basis. The precipitation efficiency of a thunderstorm is only
about 20 percent, meaning 80 percent of the moisture associated with it
remains in the atmosphere. I can provide the reference.
Cloud seeding does not divert rain from falling in one place in
favor of another (or in other words, cloud seeding does not rob Peter
of rain to `water' Paul, it provides a little more rain to Peter and
more rain to Paul than he would have received naturally). Clouds have
been observed to contain plenty of moisture, even during the early
months of a drought-period. Clouds just don't always possess a natural
precipitation initiation mechanism (virga--precipitation that doesn't
reach the ground--is not an example of a viable precipitation process,
but may occur). The absence of a viable precipitation process also
happens frequently in the areas surrounding deserts (drought regions).
Cloud seeding applied to such clouds, under the right atmospheric
conditions, provides the trigger to initiate a viable precipitation
process. So cloud seeding extends the area of precipitation beyond what
nature is able to provide. This is analogous to receiving a flu shot to
make our immune system more viable during flu season. It is mostly not
true that getting a flu shot gives us the flu. Not getting the flu shot
generally means getting the flu.

This raises similar issues as water rights controversies, where
rivers have been diverted to accommodate certain interests at the
expense of others.
Question 2. Has the scientific community considered the legal
implications of weather modification?
Answer. The legal implications of weather modification are well
documented (e.g., Ray Jay Davis, lawyer (deceased); Academic Press book
on Weather Modification by Arnett Dennis 1981; American Society Civil
Engineers (ASCE), Manual of Professional Practice for precipitation
enhancement, 2nd Edition, and the ASCE standard practice documents on
hail suppression, precipitation augmentation, and supercooled fog
dispersal seeding operations).
The scientists who regularly attend weather modification
association meetings are familiar with these implications, and efforts
have been underway to reach others. The Weather Modification
Association Public Information Committee Chair will be happy to provide
such documents to the Senator.

Question 3. Shouldn't Congress be concerned that any government
supported Weather Modification Board might support research and
development of weather modifications without considering the legal
implications?
Answer. Legal implications mostly apply to operations, and
operational seeding will not be conducted by the Federal Government
under Senator Hutchison's bill. The board is comprised of people who
have direct experience with weather modification activities.

Question 4. Have you addressed the basic question of who owns the
weather?
Answer. This is currently left to the States. Under this bill any
activity to modify the weather would have to address legal and
environmental issues before it commenced since all would have a stake
in the deliverable.
Funding
I am concerned that there are a number of areas within weather
research that are inadequately funded. For example, drought is of
particular concern to my state right now. The National Drought
Mitigation Center (NDMC) in Nebraska has only been in existence since
1995. Previously, no national initiative or program existed to monitor
drought trends. The work at the NDMC in monitoring drought, not only in
Nebraska, but nationwide, will help us mitigate and respond to its
effects in a much more effective manner. This is only one of numerous
programs addressing weather monitoring, mitigation, and response that
is years behind where it could be.
Question 1. Should funding of new research on weather modification
be a greater priority than research in the weather we already have now?
Answer. No, but funding weather modification research can lead to
additional technologies that more visibly serve societal needs, such as
providing more water for reservoirs, energy generation or more sunshine
for mental wellbeing, energy storage, reducing the destructive forces
associated with hurricanes, or drought mitigation.
If science and technology expenditures can be explicitly directed
toward resolving a societal issue, it will make it easier to obtain
public support, as society will see and appreciate that their taxes are
being used to help resolve issues they face.

Question 2. Shouldn't we ensure that existing research is
adequately funded in order to protect commercial and governmental
interests before making a commitment to support private research?
Answer. Private research support for weather modification does not
exist. Thus research related to weather modification requires some
research to understand what is to be modified. So, funding technology
development and their application also funds the existing research. The
direct benefits of funding weather modification research could be
realized in the Departments of Commerce, Interior, and Homeland
Security (tracking and removal of bioterrism agents).
______

Response to Written Questions Submitted by Hon. Bill Nelson to
Dr. Thomas P. DeFelice

Funding
The Hurricane Research Division of NOAA's Office of Atmospheric
Research has been inadequately funded for many years. As a result,
research staff vacancies have gone unfilled, years of data have gone
unanalyzed, and the science of hurricane prediction--especially with
regard to intensity--is years behind where it could be. Question 1.
Should funding of new research on weather modification be a greater
priority than research in the weather we already have now?
Answer. No, but funding weather modification research can lead to
additional technologies that more visibly serve societal needs, such as
providing more water for reservoirs, energy generation or more sunshine
for mental wellbeing, energy storage, reducing the destructive forces
associated with hurricanes, or drought mitigation.
It was envisioned that the NOAA Hurricane Research Division (HRD)
could play a significant role in weather modification research, since
HRD models represent the best available for simulating realistic
hurricanes. The unanalyzed data from previous hurricane research are
useful for conducting crude verification of select hurricane model
outputs.

Question 2. Shouldn't we ensure that government hurricane research
is adequately funded in order to protect lives before we make a
commitment to support private research in weather research that has
primarily only commercial applications?
Answer. Yes, government hurricane research must be adequately
funded, along with all weather system research. There is no known
funding authorization for private research.
______

Response to Written Questions Submitted to Michael Garstang, Ph.D.
Priorities and Funding of Atmospheric Research

Questions from Hon. E. Benjamin Nelson:
1. Should funding of new research on weather modification be a
greater priority than research in the weather we already have now?
2. Shouldn't we ensure that existing research is adequately funded
in order to protect commercial and governmental interests before making
a commitment to support private research?
Questions from Hon. Bill Nelson:
1. Should funding of new research on weather modification be a
greater priority than research in the weather we already have now?
2. Shouldn't we ensure that government hurricane research is
adequately funded in order to protect lives before we make a commitment
to support private research in weather research that has primarily only
commercial applications?
Questions from Hon. Daniel K. Inouye:
1. What is this Board's legal and line of authority relationship to
the Secretary of Commerce and the Administrator of NOAA?
2. What is the legal and scientific basis for creating such a
powerful entity?
3. The establishment of this board appears to place weather
modification research above all other types of atmospheric research as
a priority for funding within the Federal system. Why?
4. Would this Board have subpoena powers and the power to issue
``rules,'' as is suggested by the bill?
5. Is the purpose of the Board to essentially create an independent
agency dedicated to the promotion of weather modification research and
distribution of grants? Please explain.

Answers to questions 3 and 5 (questions 1, 2, and 4 were beyond the
Scope of the NRC Report).
The NRC report documents the decline in funding for research in
weather modification over the past 3 decades. Federal funding of
weather modification research declined by the 1990s to less than $0.5M/
year.
The NRC report points out the paradox between
1. funding (largely by States) of unverified weather modification
methods to address critical needs for water and reduction of damage
(hail) but failure to fund the research needed to understand and
improve these methodologies.
2. substantial application of research funds directed at
understanding and defining the implications of inadvertent weather
modification (global warming) but failure to employ resources that
would address advertent weather modification despite the fact that many
of the basic scientific principles underly both unintentional and
intentional weather modification.
The NRC report emphasizes the fact that over the past 30 years
enormous strides have been made in technology enabling processes
critical to all weather to be observed, recorded, assimulated and
modelled. Explicit attack upon critical physical processes such as the
formation of a raindrop or a hail stone is now possible. Such a
directed and sustained effort to remove obstacles to progress would pay
dividends not only in weather modification but in many areas of the
weather.
For example, one of the greatest difficulties facing a weather
forecaster is the prediction of the intensity and amount of the
expected rain and hence flooding and other damage. Understanding the
microphysics leading to rain can be significantly enhanced by carrying
out controlled weather modification experiments. This understanding of
precipitation would contribute directly to furthering our ability to
predict the intensifying or weakening of a hurricane.
The NRC report recommends a very directed research effort which
would address a series of obstacles in understanding critical
atmospheric processes. Such an effort would benefit a broad spectrum of
applications of weather science.
The NRC report explicitly advises against the application of
Federal research resources to rain enhancement or hail reduction
experiments until the critical questions blocking progress have been
addressed.
Finally, the NRC report points to the need and responsibility to
address questions of water needs, severe storm damage ranging from hail
and lightning to wind and water damage. The capability now exists to
determine whether and to what extent humans are capable of exercising
control over the weather. Unless a concerted and sustained effort is
mounted by all of those responsible such questions will remain
unanswered.

Legal Implications of Weather Modification
Questions from Hon. E. Benjamin Nelson:
1. Has the scientific community considered the legal implications
of weather modification?
2. Shouldn't Congress be concerned that any government supported
Weather Modification Board might support research and development of
weather modifications without considering the legal implications?
3. Have you addressed the basic question of who owns the weather?
Answer:
The NRC report recognized the importance of weather modification
research to society including legal implications. The NRC Committee's
terms of reference were confined to addressing the current and future
state of weather modification research.
The NRC report does, however, point out that efforts in rainfall
enhancement are directed at the redistribution and efficient use of
existing water vapor supplies in the atmosphere. Intervention could
produce rain where needed without ``robbing Peter to pay Paul''.
Research and operations which have shed light on this question suggest
instead that ``extra area'' effects extend rather than limit the
effects of rainfall enhancement.


https://www.govinfo.gov/content/pkg/CHRG-109shrg28211/html/CHRG-109shrg28211.htm

WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
1
A Plan for the next phase in Weather Modification Science and Technology
Development
T.P. DeFelice
Introduction
Weather modification science and
technology development plans have been
constructed (e.g. Schaefer, 1969, 1976;
Juisto, 1974). Those plans have lead to
modern weather modification technologies,
which have been helping the community at
large meet water resource requirements for
over 50 years. Present-day cloud seeding
technologies and the recognition of treatable
clouds are scientifically based. The scientific
community acknowledges that cloud seeding
yields a 10% increase in the amount of
precipitation (compared with normal
precipitation) that reaches the ground when
the seeding is prudently conducted under
favorable atmospheric conditions (e.g.
Weather Modification Association, 2005;
American Meteorological Society, 1998;
Elliott et al., 1995; Weather Modification
Association, 1993; World Meteorological
Organization, 1992). Apparently, some
stakeholders benefit greatly from an order of
magnitude less increase in the amount of
rainfall (compared with normal rainfall).
Weather modification technologies
may be affectively applied to facilitate the
water and energy cycles, which are key to
dealing with many present and potential
future scientific, environmental, and
socioeconomic issues. Contemporary
socioeconomic problems mostly focus on
drought. For example, there is a clear and
pressing need for additional clean water,
since it is predicted that more than 40% of
the world?s population will live in waterstressed areas by the decade of the 2020s.
There is also steadily increasing property
damage and human suffering caused by
hazardous weather (e.g., freezing rain,
severe weather), fire, and other
environmental problems (related to toxic
wastes, ozone hole, ?acid rain?, biological or
chemical warfare, CDC 2000, for example).
Technological and scientific advances have
recently yielded, new seeding material,
polarimetric radar, Doppler radar and
software, and enhanced computational
resources (e.g. Orville et al., 2000; NRC,
2003). Hence, an impetus for developing
systems that monitor and manage
atmospheric events. The atmospheric events
are treatable using proven and some new
modern weather modification technologies,
and they include hurricanes, tornadoes, and
pollutant transport. Consequently, the next
phase in weather modification science and
technology development is to outline a highlevel national program plan for developing
modern weather modification science and
technologies that takes advantage of lessons
learned, recent science and technological
advances for more effectively benefiting
society.
The ?next phase? in weather
modification science and technology
development will encompass a
comprehensive agenda of fundamental and
applied research & development efforts
directed toward optimizing existing
technologies used to manage ?treatable?
atmospheric processes and conditions, and
to allow the development of relevant
innovative technologies. It will require a
permanent, national program that
administers the resources and the activities
to develop the operational application of
atmospheric modification (weather
modification) technologies, which help
WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
2
provide sustainable water supplies and
mitigate the excessive effects from
atmospheric hazards (frozen rain,
hurricanes, tornadoes, other). This includes
improving the understanding of the relevant
processes and the evaluation methods for
operational activities as suggested by
Silverman (2001a), making use of
cooperative multi-disciplinary research and
development arrangements, and a welldesigned outreach activity.
Discussion:
Lessons learned activities, as well as
recent science and technological advances
have identified many focal areas for initial
efforts undertaken during the next phase in
weather modification science and technology
development.
There is a need to develop the ability
to better simulate, and thereby, identify and
monitor atmospheric events, airborne
pollutants, and select inadvertent weather
modification signatures. This ability
combined with improved seeding
technologies will maximize the benefit and
success of this program since they contribute
to the resolution of water-related issues
(especially water scarcity). These
improvements, when combined with
improved scientific understanding, provide a
more useful tool for determining when and
where the atmosphere or cloud can most
likely benefit from implementing the
improved or new technologies.
Developing improved dispersion
techniques and higher yield cloud seeding
agents are needed for obvious reasons. The
development of technologies to ?treat?
hazardous weather systems (e.g. freezing
rain, hail formation, tornadoes, hurricanes)
are more critically needed, and will benefit
from past and ongoing research results,
especially research using ground-, air-, and
satellite-based remote sensing devices
(radars including Doppler, lidars,
radiometers, and others). The
aforementioned need is rather ominous, but
necessary and attainable in time. Initial
efforts to develop an understanding of how
present-day cloud seeding technologies can
be applied and modified to lessen the
socioeconomic impacts of hazardous
weather events and materials might begin
with the information gained from simulating
these systems, then with these models
modify them to include the results from
applying various seeding technologies. The
modeling of seeding agent tracer study
results would greatly improve seeding agent
placement within cloud systems, and they
could form the basis for Homeland Security
needs (J. Golden, NOAA, FSL, Boulder
Co., 2004, personal communication).
The state-of-the-art cloud seeding
technologies might be ready for application
toward mitigating the effects of freezing rain
events. The knowledge base is not large
enough to reliably support tornado ?zapping?
or hurricane ?snuffing? efforts. It may one
day support these efforts after appropriately
funded and directed cooperative research
campaigns have been completed. The
existing cloud seeding technologies are
operationally used to reduce hailstone size,
and may possibly be used to reduce the
intensity of rotational hurricane winds. The
reductions in hurricane rotational wind
speeds following cloud seeding (?Esther? in
1961, ?Beulah? in 1963, and 30% for
?Debbie? in 1969), were not statistically
distinguishable from the range of natural
variability, and is not yet scientifically
accepted. Consequently, modeling studies
should dominate these efforts, initially.
Simulation and modeling studies will
require verification. This should be accomplished
WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
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through carefully designed cooperative efforts.
Cloud seeding program evaluations also need to
be improved. Evaluations require revisiting
whether measuring devices used for evaluations
are primary standards, if not, does one exist, if so
is there a better device? For example, is the
standard precipitation gauge truly a primary
standard for precipitation amount measurements?
That is, does it represent the natural spatial and
temporal precipitation amount field (e.g. DeFelice,
1998) under all conditions, or better than
alternative measuring devices? The answer is
crucial to evaluating the success of precipitation
augmentation projects, for example. If not, could
the Z(reflectivity) - L(precipitation water content)
relationship be used to estimate rainfall amount?
The Z-L would not require estimates of
hydrometeor terminal velocity, and L can be
verified using a dual wavelength microwave
radiometer.
Inadvertant modification studies
need to be increased, and not solely from a
climate change point-of-view. For example,
a land cover change from agricultural to
urban over a modest area can introduce a
climatic forcing similar in magnitude and
direction to that from carbon dioxide (R.
Pielke Sr., 2001, personal communication).
Here initial efforts should at least focus on
strategies for (a) minimizing the effect from
inadvertent modifications to the atmosphere,
and (b) neutralizing airborne pollutants
within cloud systems or redirecting their air
trajectories to settle on ?safe surfaces?.
The plan, derived from past lessons
learned, including DeFelice (2002), must
address the current and near future needs of
the WMA community and also provide the
high-level infrastructure to address the
recommendations from the parent science
community (Table 1). Table 1 summarizes
how the plan objectives align with
recommendations from the National
Research Council (NRC). This plan will
benefit from project management process
improvement exercises currently underway
by the author.
It is important to make clear that the
implementation of this plan calls for tackling
tasks, issues within components (i), (ii), and
(iii) in a multi-disciplinary, cross-component
environment that exists throughout the
entire life cycle of the plan. This is
accomplished by
(i) specifying well-defined plan
member roles and responsibilities
at all levels within the plan at the
plan?s kickoff meeting.
(ii) Developing carefully designed
cooperative research and
development efforts whose
purpose is to enhance the
understanding of the inherent
multi-disciplinary processes for
the good of the operational WMA
community. This has economic
benefits to the program as well.
Furthermore, the plan must have
somebody, i.e., functional area lead,
chartered to ensure that matured plan
technologies are transferred to stakeholders
and end users in a timely fashion.
The alternative could repeat
historical performance.

Table 1. This plan versus NRC 2003 plan recommendations
1. This plan assumes a permanent, national
(if not international) program that would
administer the resources and the activities for
all research and development efforts directed
toward optimizing the technologies used to
manage the efficiency of atmospheric
hydrological processes.
1. ?Because weather modification could
potentially contribute to alleviating water
resource stresses and severe weather
hazards, ? A renewed commitment to
advancing our knowledge of fundamental
atmospheric processes central to the issues
of intentional and inadvertant weather
modification ....?
2. This plan outlines a comprehensive
agenda of fundamental and applied research and
development efforts directed toward optimizing
the technologies used to operationally manage
the efficiency of atmospheric hydrological
processes to help provide sustainable water
supplies. See Resource Requirements
2. ?Coordinated research program
includes? Carry out exploratory and
confirmatory experiments ? Hygroscopic
seeding ?Orographic Seeding ? Studies
of specific seeding effects ??.
?Capitalizing on existing field facilities
and developing partnerships among
research groups and select operational
programs.?
3. This plan calls for developing:
-better monitoring capabilities for all
atmospheric events, including frozen rain,
hurricanes & tornadoes, airborne pollutants.
-more effective dispersion techniques
-higher yield seeding agents for warm & cold
clouds
-improved evaluation protocols.
-strategies to minimize inadvertent weather
modification.
3. ?? coordinated national program
be developed to conduct a sustained
research effort in the areas of cloud and
precipitation microphysics, cloud
dynamics, cloud modeling, laboratory
studies and field measurements designed
to reduce key uncertainties ??

WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
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Program Organization:
The plan program would be organized into
five functional areas as shown in Figure 1,
and would have initial goals, based on
lessons-learned and recent scientific -
technological advances, that are similar to
the following.
Weather Modification Event
Monitoring/Analysis Prediction System
Development
Goals- (i) High resolution
monitoring/analysis prototype systems able
to identify the atmospheric conditions
conducive to beneficial precipitation
augmentation, hail suppression, and other
hazardous storm suppression (freezing rain,
hurricanes, tornadoes, other). (ii) Transfer
information to the Professional
Development/Public Outreach activity.
Glaciogenic and Nonglaciogenic Seeding
Technology Research/Development
Goals- (i) Better nucleation efficiency of
possible warm cloud, cold cloud, and other
?cloud? seeding materials. (ii) More efficient
delivery (dispersion) systems for a given
application as identified under (i). (iii)
Transfer results to Professional
Development/Public Outreach activity.
Applications Research/Development
Goals- (i) Improved evaluation
methodologies. (ii) Operational atmospheric
management monitoring/analysis prediction
systems. (iii) (a). Verified high resolution
models with explicit microphysics for
understanding Hazardous storms,
inadvertent modification of atmospheric
conditions, and other associated
phenomenon (environmental and as
directed). (b) Implement (iii, a) with seeding
material introduced. (iv) Improved targeting
systems. (v) Improved applicability of
evaluation technologies (e.g. dual, polarized,
Doppler radars, tracer techniques). (vi)
Transfer systems and results to professional
development/public outreach activity for
feedback on operational usefulness, and finetune them based on users? input.
Professional Development, Public Outreach
Goals- (i) Develop and present educational
materials, demonstrations, workshops, and
colloquia that emphasize the relevant
applications derived from this program?s
activities and related technologies. (ii)
Coordinate the technology transfer to
program customers. (iii) Conduct interactive
open houses with public
Plan Management and Support
Goals- (i) Provide overall programmatic
metrics, guidance, and support during the
life of this program. (ii) Participate in the
definition and development of future and
related technology investigations. (iii)
Administer seed grants for innovative or
new applied research and applications.
The triangle in Figure 1 symbolizes the
interdependence of these functional plan
areas. A core group consisting of the
necessary skill mix to comprehensively
address the underlying issue, and a
representative from the end user should be
assigned to each objective.
Program Objectives:
The initial program-wide objectives are:
1. Develop a system to identify and
monitor all atmospheric environmental
WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
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conditions that are good candidates for
beneficial modification through its
developed technologies.
2. Develop technologies to more
efficiently treat
a. traditional cold and warm
cloud systems
b. weather and environmental
hazards
3. Validate/verify the operational and
computational aspects of weather
modification technologies and systems
developed under this program.
4. Develop strategies to minimize the
effects from the inadvertent
modification of atmospheric conditions
(formerly termed inadvertent weather
modification).
5. Create a proactive professional
development and public outreach
activity ....

Resource Requirements (anticipated):
This program would require a budget
adequate for successful fulfillment of its
objectives. Precedent is set by successful
medical and other science programs,
wherein substantial, long-term, committed
funding has lead to positive results. Making
such an investment for this plan very soon
and continuing it through the decade of the
2040?s, will most probably ensure that
significantly less than 40% of the world?s
population will reside in water-stressed
areas, for example.
Office and some laboratory space
will be required, and should be capable of
housing 120 employees. An east coast
location would maximize the benefit from
interacting with NOAA, DoD, DOE, DOI,
NASA, other government centers and
laboratories, and other relevant
organizations. There should never be less
than 70-80 FTEs for support and technical
staff, 5-10 FTEs for student interns, and 15-
20 FTEs for all program administrative staff.
DeFelice (2002) provided a breakdown
between FTEs and high-level activity (i.e.,
titles in Figure 1 objects). The laboratory
space could be used for data analyses,
experimental cloud studies to develop
modeling algorithms, nucleation
experimentation with ice, water, and perhaps
other substances (such as polymers, etc.), as
well as the development of instrumentation
and information technology applications that
are especially relevant to the data collected
and analyzed through this program. This
could include the development of 3 state-ofthe art cloud chambers to study ice, water
and other species nucleation. The
laboratory should also house computers
capable of archiving and processing large
volumes (i.e., mega terabytes) of multidisciplinary data in near real-time,
instrumentation storage compartment(s), an
area for instrument calibration, and other
standard laboratory ware, as appropriate.
Cooperative Agreement Candidates
(anticipated): This plan must contain
cooperative agreements (or equivalent, i.e.,
MOUs- memorandums of understandings)
with the National Center for Atmospheric
Research, Research Applications Program,
already dedicated to atmospheric
modification activities, research aircraft and
relevant resources at the South Dakota
School of Mines and Technology Institute of
Atmospheric Sciences, University of North
Dakota, Weather Modification Inc., NOAA,
and the University of Oklahoma MESONET
to help with various aspects of model
development/ validation efforts and other
physical studies. The agreements should
also be extended to Woodley Associates,
North American Weather Consultants,
Atmospherics Incorporated, as well as other
relevant companies, organizations,
universities, and government agencies (e.g.,
those in Texas, Nevada, and Kansas,
Colorado State University, NOAA National
Severe Storms laboratory, the USGS/U.S.
Navy/U.S. Department of Agriculture/CDC
research team-Bozeman, Montana, and the
USGS/EDC teams for Land Use Dynamics,
Applications Research, & Remote Sensing
Systems).
Programmatic Success: The likelihood of
success is high, because the program is
starting with proven technologies, many of
which have had more than 50 years to
mature.
The success of this program will be
gauged by determining whether or not its
annual tasks have been met as planned and
within cost; the ability of its outreach
program to transfer program technologies to
program customers. Surely, it is expected
that there will be improved products,
WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
9
processes and field procedures; scientific
publications and conference presentations.
Success does not require new tools,
demonstrations of significant seeding
signatures, or creation of new scientific
disciplines. Consequently, future
applications of this technology have a higher
potential for success, and less risk than that
of previous weather modification (or
atmospheric management) programs.
Risk Identification and Management:
The primary risks are likely to be losses of
key personnel, funding, required data and
technology, and systems.
? Loss of key personnel will be anticipated
by management through open
communication with government staff,
unless a contractor is hired to handle the
services contract. If a contractor
handles the services contract, then loss
of key personnel will be anticipated
through open communications with
government and contract staff. The
contractor's hiring capacity will be used
to fill vacancies as quickly as possible.
The contractor could be a particular
government agency, an
intergovernmental committee, or a nongovernment organization. Here it is
assumed that a non-government
organization will handle the services
contract since this is the current trend.
? Loss of internal agency funding
allocation will be mitigated by (1)
identifying and taking on reimbursed
research that concerns similar interests
and applications, or by (2) rescoping,
postponing, or canceling the affected
research endeavor.
? Loss of required data and systems will
be anticipated in the planning process,
and suitable proxy data or alternative
systems will be identified for quick
access if needed.
Program Customers: Program customers
potentially come from the following entities:
Farmers, crop insurance industry, water
district managers, utility industry, relevant
organizations (e.g., WMA, Environmental &
Water Resources Institute-EWRI), scientific
community, and government agencies (e.g.,
National Oceanic and Atmospheric
Association-NOAA, Environmental
Protection Agency-EPA, National
Aeronautics Space Administration-NASA,
Department of Defense-DoD, Centers for
Disease Control and Prevention-CDC;
foreign).
Anticipated Sources of Funding: Farmer
groups, insurance industry, water districts,
utility industry, State Governments, NOAA,
Congress, and others, such as the Office of
Federal Coordination for Meteorology
(OFCM).
Deliverables: (Initial, anticipated
programmatic, not annual, deliverables)
! Proven systems to monitor and
analyze all atmospheric
environmental conditions (e.g. frozen
rain, hurricanes, tornadoes, air
pollutants) that are favorable for the
beneficial modification through
technologies developed by its
activities
! Improved evaluation protocols and
technologies
! More effective atmospheric
modification technologies for
traditional, weather and atmospheric
environmental hazard applications.
For example:
o Higher yield seeding agents
for warm and cold cloud
systems
o More effective dispersion
techniques

WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
10
! A strategy to minimize the possible
negative effects resulting from the
inadvertent modification of our
atmosphere
! A proactive professional
development, public outreach
program.
Closing Remarks:
This paper describes a high-level plan
for the ?next phase? in weather modification
science and technology development, made
in response to recent technological and
scientific advances and socioeconomic
issues. It will encompass a comprehensive
agenda of fundamental and applied research
& development efforts directed toward
optimizing existing technologies used to
manage ?treatable? atmospheric processes
and conditions, and to allow the
development of relevant innovative
technologies. It will require a permanent,
national program that administers its
resources and oversees its activities.
Highlights of the proposed plan
include:
! Based on many lessons learned during
the past 50 years
! Five functional components
(i). Weather Modification Event
Monitoring/Analysis Prediction
System Development
(ii). Glaciogenic and Nonglaciogenic
Seeding Technology
Research/Development
(iii). Applications
Research/Development including
evaluation
(iv). Professional Development, Public
Outreach
(v). Management Support
! It approaches tasks, issues within its
components, especially (i), (ii), and (iii),
in a multi-disciplinary, cross-component
environment that exists throughout the
entire life cycle of the plan. This is
partially accomplished by specifying all
plan member roles and responsibilities
at the plan?s kickoff meeting,
cooperative agreements, and a well
designed technology transfer activity.
! The plan encompasses the
recommendations of a NRC (2003)
report, Silverman et al (2001a, b), &
others, while addressing the near
future needs of the WMA community

Acknowledgments: The contents of this
paper do not necessarily reflect the views of any
government agency or Raytheon Company and
its business units, especially Raytheon Technical
Services Co, ITSS. The comments of Mr.
Robert Black, Manager, Program Engineering
Office, Contractor at EDC, two anonymous
reviewers of a previous version of this paper are
appreciated. The review of this paper by Dr. Joe
Golden is greatly appreciated.

WMA Annual Meeting, San Diego, Ca. 2005; 16th Weather Modification Conf. 1.1
11
References:
American Meteorological Society, 1998.
Capability statements. Bulletin American
Meteorological Society (BAMS), 79, 2771.
CDC, Centers for Disease Control, 2000.
Biological and chemical terrorism: Strategic
plan for preparedness and response.
MMWR, 49, Apr 21, RR-4, 1-14.
Avail.http://www.bt.cdc.gov.
DeFelice, T.P., 1998. Introduction to
Meteorological Instrumentation and
Measurement, Prentice Hall, Saddle Brook,
New Jersey.ISBN:0-13-243270-6.
DeFelice, T.P., 2002. A high-level
atmospheric management program plan for
the new millennium. J. Weather Modification (JWM), 34(Non Reviewed), 94-99.
Elliott, R.D., Keyes, Jr, C.G., and Reinking,
R.F., 1995. ?Summary?. In: Guidelines for
Cloud Seeding to Augment Precipitation,
Section 1. ASCE Manuals and Reports on
Engineering Practice No. 81. ASCE, Reston,
VA, pp. 1-7.
Golden, J., 2004. NOAA, FSL, Boulder
Co., Personal Communication.
Orville, H., et al., 2000. New opportunities
in weather research, focusing on reducing
severe weather hazards and providing
sustainable water resources. Report to
Nat?l Academy of Sciences for assessing the
current state of weather modification science
as a basis for future environmental
sustainability and policy development.
Available from the Institute of Atmospheric
Sciences, South Dakota School of Mines &
Technology, 501 E. Saint Joseph St., Rapid
City, SD 57701-3995. SDSMT/IAS/R00/03. December. 74 pp.
Pielke, Roger, Sr., 2001. Dept. Atm. Sci.,
Colorado State Univ., Personal
Communication.
Juisto, J.E., 1974. Weather Modification
Outlook-1985 projection. JWM, 6, 1-16.
NRC (National Research Council), 2003.
Critical Issues in Weather Modification
Research Report. National Academies
Press, Washington, DC (www.nap.edu/
openbook/0309090539/html/R1.html), 123
pp + 8 plates.
Schaefer, V.J., 1969. After a quarter
century. J. Weather Modification, 1-
nonreviewed, 1-4.
Schaefer, V.J., 1976. The future of weather
modification. J. Weather Modification, 8,
127-128.
Silverman, B.A., 2001a. A critical
assessment of glaciogenic seeding of
convective clouds for rainfall enhancement.
BAMS, 82, 903-923.
Silverman, B.A., 2001b. Comments on ?A
critical Assessment of glaciogenic seeding of
convective clouds for rainfall enhancement.? Reply. BAMS, 82, 2848-2849.
Weather Modification Association, WMA,
1993. Weather Modification capability
statement. J. Weather Modification, 25, 11.
Weather Modification Association, WMA,
2005. Weather Modification capability
statement. J. Weather Modification, In
Press.
World Meteorological Organization, 1992.
WMO statement on the status of weather
modification. J. Weather Modification, 25,
1-6.

Weather Modification Association Capability Statement. "2005" search

WEATHER MODIFICATION ASSOCIATION (WMA) POSITION STATEMENT ON
THE ENVIRONMENTAL IMPACT OF USING SILVER IODIDE AS A CLOUD
SEEDING AGENT
JULY 2009
The Weather Modification Association (WMA) is occasionally asked to comment on
questions regarding the environmental effects of silver iodide aerosols used in cloud seeding,
which include silver iodide aerosol complexes such as silver iodide-silver chloride. Silver iodide
is the primary component of silver iodide-based ice-nucleating complexes used in cloud seeding,
and all these complexes will be referred to as silver iodide (AgI) in this statement. The published
scientific literature clearly shows no environmentally harmful effects arising from cloud seeding
with silver iodide aerosols have been observed; nor would they be expected to occur. Based on
this work, the WMA finds that silver iodide is environmentally safe as it is currently being
dispensed during cloud seeding programs.


Background
Silver and chemical compounds containing silver are used by various industries and small
portions of this silver are emitted into the environment as a process waste product. Industrial
sources were much larger in the past than they are today; notable sources include silver emissions
from the photographic and electrochemical plating industries, urban refuse, sewage treatment
plants, specialty metal alloy production and electrical components. In 1978 an estimated 2,740
metric tons (metric ton = 1,000 kg) of silver were released into the US environment. This led the
US Health Services and EPA to conduct studies regarding the potential for environmental and
human health hazards related to silver.

These agencies and other state agencies applied the Clean
Water Act of 1977 and 1987 to establish regulations on this type of pollution. Standards were
established for industry and laboratory disposal practices of drain water into sewer systems, safe
silver limits in the public water supply, and thresholds of adverse effects of silver on the
biosphere. In 1978 cloud seeding activities were the source of about three metric tons of silver
(as silver iodide) released into the environment, or about 0.1 per cent of the total (Eisler 1996).
About the same amount of silver iodide is being used annually for cloud seeding activities in the
U.S. and Canada today. Cloud seeding activities release silver iodide to the atmosphere over
specific areas of the western states of the U.S., Canada and some other areas around the globe to
augment rainfall, augment snowfall or reduce hail damage. Environmental impact studies related
to silver iodide usage in cloud seeding were conducted starting in the 1960s and continue to be
conducted today; all findings to date indicate no adverse environmental and human health impacts
(ASCE 2004, 2006; WMA 2005; WMO 2007).

How much silver is released into the environment by cloud seeding?
Silver iodide is usually sold by commercial chemical company distributors in granular or
powder form. It is used in combination with various other chemicals, most often salts, and has
been used for half a century as a glaciogenic agent (microscopic sized particles, referred to as ice
nuclei, ice forming nuclei, or occasionally freezing nuclei, that spawn ice crystal formation).
Silver Iodide is considered water insoluble (solubility constant at 10-9
g[of Ag] g
-1
[of solventwater]; see units note), which means that if one gram of the chemical is added to one gram of
water, roughly one billionth of that gram of silver iodide would dissolve in to the water; the
remainder will stay in the water undissolved. This property allows the silver iodide particles to
maintain their structure prior to contact with supercooled (colder than freezing) cloud droplets.
Silver iodide, as used in cloud seeding, is either dissolved in a flammable solution or combined
with other flammable solids to produce seeding flares or other devices, which are burned to
release submicron-sized, virtually invisible, silver iodide aerosol complexes into the atmosphere.
These complexes are plentiful in number and increase the probability of ice crystals forming
when they reach cloud environments at temperatures near or colder than the AgI ice nucleation
(or crystallization) temperature threshold (about -5?C). This is significantly warmer than the
threshold of most naturally occurring ice-forming nuclei, which commonly have thresholds near -
15?C and colder.

Only small quantities of seeding material are released from individual cloud seeding
generators typically in the range of 5-25 grams of silver iodide per hour from ground generators
and up to a few kilograms per hour from aircraft depending on the size of the target area.
Moreover, this is being done only during certain periods and locations of precipitation-producing
weather systems. The reason that such small quantities can be used is that AgI dispensing
systems generally produce up to 1015 (see power of 10?s note) ice forming nuclei per gram of AgI
expended (e.g., ASCE 2004, 2006). This means small amounts of AgI seeding material can
produce tremendous numbers of ice crystal seeds that can create ice crystals, which can grow into
snowflakes. The insolubility of AgI is a crucial factor for such small particles that allows them to
maintain their identity (structure) intact and not condense water (and thus lose their structure)
inside a cloud droplet. Without this property there would be no cloud seeding effect.

As a metric of cloud seeding chemicals, silver concentrations have been measured in the
snowpack of several cloud seeding target areas in the western U. S. The average concentrations
throughout the snowpack have generally ranged from 4-20 x 10-12
g[of Ag] g
-1
[of solvent-water],
rarely exceeding 100.0 x 10-12
g g-1
(Warburton et al. 1995a,b, 1996; McGurty 1999). Since
seeding clouds could lead to rain (if snowflakes melt during their fall to earth) measurements of
seeding chemical concentrations in the rainwater have also been done and found to be in similarly
low concentrations (e.g., Sanchez et al. 1999).
Why is there concern about using silver iodide in cloud seeding?
It is well established that silver in some forms can be toxic to lower organisms without
being toxic to higher animals (Kotrba 1968). Numerous controlled laboratory studies have shown
that silver, silver nitrate and even silver iodide when added to laboratory aquariums, even at trace
levels, can be toxic to some fish and other aquatic life when exposed over long time periods; the
toxicity is related to specific compounds, concentrations and other factors such as water hardness,
etc (e.g., Davies & Goettl 1978). However, these laboratory conditions bear little resemblance to
outdoor freshwater bodies where the mobility of any of these silver compounds is essentially zero
and these compounds are rapidly converted to less toxic compounds by the presence of other
chemicals found in nature. Hence, they are not freely bio-available to the environment.
Laboratory results derived from biological studies cannot be taken to imply any meaningful
information about silver iodide used in cloud seeding because its insoluble nature makes it nearly
impossible to dissociate sufficiently or rapidly enough to ever achieve toxic levels. Meaningful
evaluation must include the specifics of the chemical form of silver (i.e., ionic silver, silver
nitrate, silver iodide), the quantities involved, and the chemical, even physical, nature of the
environment. Hence, care must be taken when comparing the potential impact of silver iodide on
the environment as used in cloud seeding programs with the impact of silver or soluble silver in
laboratory settings, which are not representative of the natural environment where cloud seeding
is conducted.
Basis for asserting that cloud seeding using silver iodide has negligible environmental impact.
The potential environmental impacts of cloud seeding programs using silver iodide have
been studied since the 1960s. These studies have all concluded that ice-nucleating agents, specifically silver iodide as used in cloud seeding, represent a negligible environmental hazard,
(i.e., findings of no significant effects on plants and animals), (e.g., Cooper & Jolly 1970; Howell
1977; Klein 1978; Dennis 1980; Harris 1981; Todd & Howell 1985; Berg 1988; Reinking et al.
1995; Eliopoulos & Mourelatos 1998; Ouzounidou & Constantinidou 1999; Di Toro et al. 2001;
Bianchini et al. 2002; Tsiouris et al. 2002a; Tsiouris et al. 2002b; Christodoulou et al. 2004;
Edwards et al. 2005; Keyes et al. 2006; Williams & Denholm 2009).
The U.S. Public Health Service established a concentration limit of 50 micrograms of
silver per liter of water in public water supply to protect human health (e.g., Erdreich et al. 1985).
The concentrations of silver potentially introduced by modern cloud seeding efforts are
significantly less than this level. The literature embodies tens of thousands of samples collected
from cloud seeding program areas over a thirty-year period showing the average concentration of
silver in rainwater, snow and surface water samples is typically less than 0.01 micrograms per
liter. More importantly, these measurements represent the total amount of silver contained in any
given sample and are not specific to the form of silver present in a sample. Nevertheless, these
measurements show that silver is virtually undetectable in any form in the vast majority of the
tens of thousands of samples collected from these areas.
More than 100 Sierra Nevada lakes and rivers have been studied since the 1980?s (e.g.,
Stone 1986); no detectable silver above the natural background was found in seeded target area
water bodies, precipitation and lake sediment samples, nor any evidence of silver accumulation
after more than fifty years of continuous seeding operations (Stone 1995; Stone 2006). Many of
these alpine lakes have virtually no buffering capacity, making them extremely susceptible to the
effects of acidification and sensitive to changes in trace metal chemistry. Therefore studies were
conducted as part of environmental monitoring efforts to determine if cloud seeding was
impacting these lakes. No evidence was found that silver from seeding operations was detectable
above the background level. There was also no evidence of an impact on lake water chemistry,
which is consistent with the insoluble nature and long times required to mobilize any silver iodide
released over these watersheds. Comparisons of silver with other naturally occurring trace metals
measured in lake and sediment samples collected from the Mokelumne watershed in the Sierra
Nevada indicate that the silver was of natural origin (Stone 2006). Similarly, Sanchez et al.
(1999) analyzed the chemistry of water bodies and rainwater from samples collected during a
summer cloud seeding program in Spain, and determined the silver input from cloud seeding to be
indistinguishable from natural inputs. Greek scientists studying the effects on soils, plants and
their physiology, atmospheric precipitation, plankton, animals and man, as well as the impact of
irrigation and organic matter to AgI leaching from the Greek cloud seeding activities found
similar results following the analyses of 2500 soil samples (e.g., Tsiouris et al. 2002a; Tsiouris et
al. 2002b).
Summary
The published scientific literature clearly shows no environmentally harmful effects
arising from cloud seeding with silver iodide aerosols have been observed, nor would be expected
to occur. Based on this work, the WMA finds that silver iodide is environmentally safe as it is
currently being used in the conduct of cloud seeding programs.

Bibliography
ASCE (2004). ?Standard Practice for the Design and Operation of Precipitation Enhancement
Projects?. ASCE(American Society Civil Engineers) /EWRI Standard 42-04, Reston, VA.
ASCE (2006). ?Guidelines for Cloud Seeding to Augment Precipitation?. 2nd Edition. American
Society Civil Engineers(ASCE)/EWRI, Reston, VA.
Berg, N.H. (1988). A Twelve-Year study of environmental aspects of weather modification in the
Central Sierra Nevada and Carson Range. The Sierra Ecology Project, Unpublished report on
file at Pacific SW Res. Station, Forest Service USDA, Albany CA.
Bianchini, A., M. Grosell, S.M. Gregory, C.M. Wood (2002). Acute silver toxicity in
aquatic animals is a function of sodium uptake rate, Env. Sci. &Techn., 36, 1763-1766.
Christodoulou, Μ., S. Tsiouris, I. Papadoyannis, F. Aravanopoulos, I. Vlemmas, D. Mourelatos,
S. Mourelatos, H.-L. Constantinidou (2004). Determination and impact of silver iodide on
terrestrial and aquatic ecosystems of areas where cloud seeding has been applied. Proceedings
of the 7th Panhellenic (International) Conference of Meteorology, Climatology and
Atmospheric Physics, Volume A, 195-203.
Cooper, C.F., W.C. Jolly (1970). Ecological Effects of Silver Iodide and other Weather
Modification Agents: A review. Water Resources Research, 6, AGU, 88-98.
Davies, P.H., J.P. Goettl, Jr. (1978). Evaluation of the potential impacts of silver and/or silver
iodide on rainbow trout in laboratory and high mountain lake environments. In: Environmental
impacts of artificial ice nucleating agents. Klein, D.A. (Ed.). Dowden, Hutchinson and Ross
Inc., Stroudsburg, PA.
Davies, P.H., J.P. Goettl, Jr., J.R. Winley (1978). Toxicity of silver to rainbow trout (Salmo
gairdneri). Water Res., 12, 113-117.
Dennis, A. S. (1980). ?Weather Modification by Cloud Seeding?. International Geophysics
Series, 24, Academic Press, New York, NY, 21-22.
Di Toro, D.M., H.E. Allen, H.L. Bergman, J.S. Meyer, P.R. Paquin, R.C. Santore (2001). Biotic
Ligand Model of the acute toxicity of metals. 1. Technical basis. Environmental Toxicology
and Chemistry, 20, 2383-2396.
Edwards, R., A. Huggins, J. McConnell (2005). ?Trace Chemistry Evaluation of the Idaho Power
Company Operational Cloud Seeding Program 2003 to 2005?. DRI Publication #41223.
Eisler, R. (1996). Silver Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review,
Contaminant Hazard Reviews, 32, Patuxent Wildlife Research Center, U.S. National
Biological Service, Laurel, MD.
Eliopoulos P., D. Mourelatos (1998). Lack of genetoxicity of Silver Iodide in the SCE Assay in
vitro, in vivo, and in the Ames/Microsome Test. Terratogenesis, Carcinogenesis and
Mutagenesis, 18, 303-308.
Erdreich, L., R. Bruins, J. Withey (1985). Drinking Water Criteria Document for Silver (Final
Draft). U.S. EPA, Washington, D.C., EPA/600/X-85/040 (NTIS PB86118288).
Harris, E. (1981). ?Environmental Assessment and Finding of No Significant Impact?. Sierra
Cooperative Pilot Project, Bureau of Reclamation, Denver, Co.
Howell, W. E. (1977). Environmental impacts of precipitation management: Results and
inferences from Project Skywater. Bull. Amer. Meteor. Soc., 58, 488-501.
Keyes, et al. (2006). ?Guidelines for Cloud Seeding to Augment Precipitation?. 2nd Edition.
American Society Civil Engineers, Reston, VA.
Kotrba, G. (1968). "The Encyclopedia of the Chemical Elements", Hampel, C. A., Editor,
Reinhold Book Corporation, New York, Amsterdam, and London.
Klein, D.A. (1978). "Environmental Impacts of Artificial Ice Nucleating Agents" Colorado State
University, Dowden, Hutchinson & Ross, Inc. Library of Congress Catalog Card Number, 78-
7985.
McGurty, B. M. (1999). Turning silver into gold: Measuring the benefits of cloud seeding.
HydroReview, 18, 2-6.

Ouzounidou G., H.-I.A. Constantinidou (1999). Changes in growth and physiology of tobacco
and cotton under Ag exposure and recovery. Are they of direct or indirect nature? Arch.
Environ. Contam. Toxicol., 37, 480-487.
Reinking, R.F., N.H. Berg, B.C. Farhar, O.H. Foehner (1995). ?Economic, Environ-mental, and
Societal Aspects of Precipitation Enhancement by Cloud Seeding,? Manual 81, Guidelines for
Cloud Seeding to Augment Precipitation, ASCE, Reston, VA, 9-47.
S?nchez, J. L., J. Dessens, J.L. Marcos, J.T. Fern?ndez (1999). Comparison of rain-water silver
concentrations from seeded and non-seeded days in Leon (Spain). J. Weather Mod., 31, 87-90.
Stone, R.H. (1986). ?Sierra Lakes Chemistry Study.? Final Report to Southern California Edison
Co., Contract No. C2755903.
Stone, R.H., K. Smith-Miller, P. Neeley (1995). Mokelumne Watershed Lake Water and
Sediment Silver Survey. Final Report to the Pacific Gas and Electric Company, Technical and
Ecological Services, San Ramon, Ca.
Stone, R.H. (2006). ?2006 Mokelumne Watershed Lake Water and Sediment Survey.? Final
Report to the Pacific Gas and Electric Company, Technical and Ecological Services, San
Ramon, Ca.
Todd, C.J., W.E. Howell (1985). ?Weather Modification?. In Handbook of Applied
Meteorology, David D. Houghton, Editor, John Wiley and Sons, Chapter 38, 1065-1139.
Tsiouris E.S., A.F. Aravanopoulos, N.L. Papadoyiannis, K.M. Sofoniou, N. Polyzopoulos, M.M.
Christodoulou, F.V. Samanidou, A.G. Zachariadis, H.-I.A. Constantinidou (2002α). Soil
Silver Content of Agricultural Areas Subjected to Cloud Seeding with Silver Iodide. Fresenius
Environmental Bulletin, 11, 697-702.
Tsiouris E.S., A.F. Aravanopoulos, N.L. Papadoyiannis, K.M. Sofoniou, F.V. Samanidou, A.G.
Zachariadis, H.-I.A. Constantinidou (2002b). Soil Silver Mobility in Areas Subjected to Cloud
Seeding with AgI. Fresenius Environmental Bulletin, 12, 1059-1063.
Warburton, J.A., L.G. Young, R.H. Stone (1995a). Assessment of seeding effects in snowpack
augmentation programs: Ice nucleation and scavenging of seeding aerosols. J. Appl. Meteor.,
34, 121-130.
Warburton, J.A., R.H. Stone, B.L. Marler (1995b). How the transport and dispersion of AgI
aerosols may affect detectability of seeding effects by statistical methods. J. Appl. Meteor., 34,
1929-1941.
Warburton, J.A., S.K. Chai, R.H. Stone, L.G. Young (1996). The assessment of snowpack
enhancement by silver iodide cloud-seeding using the physics and chemistry of the snowfall. J.
Weather Mod., 28, 19-28.
Weather Modification Association (2005). ?Weather Modification Association Capability
Statement.? WMA; www.weathermodification.org/capabilities.htm.
Williams, B.D., J.A. Denholm (2009). Assessment of the Environmental Toxicity of Silver
Iodide-With Reference to a Cloud Seeding Trial in the Snowy Mountains of Australia. . J.
Weather Mod., 41, 75-96.
World Health Organization (2002). ?Concise International Chemical Document 44 (CICAD44):
Silver and silver compounds: Envionmental Aspects.? WHO; www.inchem.org/documents/
cicads/cicads/cicad44.htm
World Meteorological Organization (2007). ?WMO Statement on Weather Modification.? WMO;
www.wmo.int/pages/prog/arep/wmp/documents/WM_statement_guidelines_approved.pdf.
NOTES:
Following are intended to help non-technically trained readers understand information provided above.
Power of 10?s note: Very large and very small numbers are often expressed in scientific or powers of 10 notation.
The 1015 stated in the WMA statement means that 1 is 10 multiplied by 10, 15 times and it equals
1,000,000,000,000,000. When 10 is raised to a negative power it means 1 divided by 10 the power number of times;
for example, 1 x 10-1 equals 0.1.
Units note: g g-1
as used here means grams of chemical divided by grams of water in the sample, so that 1 x 10-12 g
g
-1 means 0.000000000001 grams of silver per 1.0 grams of water

http://countyofsb.org/uploadedFiles/pwd/Content/Water/WaterAgency/WMA%20AGI_toxicity.pdf

 

WMA Capabilities Statement on Weather Modification
Adopted April 2016
Capabilities Statement

Background
Under certain atmospheric conditions cloud microphysical and precipitation processes can be
intentionally modified using existing cloud seeding methodologies to yield beneficial effects.
Beneficial effects are those in which favorable benefit/cost ratios are realized without
producing detrimental environmental impacts. The magnitudes and temporal/spatial scales of
beneficial cloud seeding effects vary between project types and location. This statement covers
the intentional application of cloud seeding technology and techniques (described below)
covering areas from a few to several thousands of square kilometers for periods of hours to
days. Larger-scale efforts to intentionally modify weather and climate regionally or globally
using cloud-seeding or other technology and techniques, commonly referred to as
geoengineering, are excluded from this discussion.

Increasing demands are being placed upon existing fresh water supplies throughout the world.
These increasing demands lead to greater sensitivity to drought and to moderate precipitation
shortfalls. Recent investigations have indicated that negative impacts of air pollution on
precipitation downwind of some industrialized areas are probable. Concerns about water
supplies are increasing interest in using cloud seeding techniques for precipitation
augmentation. Hail damage to crops and property and fog-induced problems continue to
produce interest in their mitigation. These factors, combined with the typically attractive
benefit/cost ratios associated with operational cloud seeding projects, have fostered ongoing
and growing interest in intentional weather modification.

Brief capability statements regarding intentional weather modification by cloud seeding follow,
summarizing the current state of the technology within the primary application categories. The
summaries are limited to conventional cloud seeding methods that are based on accepted
physical principles. Regional differences in cloud microphysics, atmospheric temperature,
frequency of seedable cloud system occurrence, orographic influences, seeding agent selection,
delivery and dosage rates, and quality and completeness of operational execution, can alter
these expectations. A more detailed treatment of weather modification capabilities, position
statements, and the status of the discipline can be found in Guidelines for Cloud Seeding to
Augment Precipitation, 3rd Edition, ASCE Manuals and Reports on Engineering Practice No. 81,
American Society of Civil Engineers, Reston, VA, 2016.

The potential environmental impacts of cloud seeding have been addressed in many studies.
No significant adverse environmental impacts have been found due to use of silver iodide, the
most commonly used seeding material, even in project areas where seeding has been
conducted for fifty years or more. A more comprehensive discussion on environmental
implications of using silver iodide in cloud seeding along with references can be found in a
published WMA policy statement, The Environmental Impact of Using Silver Iodide as a Cloud
Seeding Agent, July 2009, (WMA website, http://weathermod.org/aboutus/).

Claims regarding other methods of intentional weather modification involving hail cannons and
ionization generators have not been scientifically substantiated to date. The Weather
Modification Association does not currently endorse those methods.

Fog and Stratus Dispersal
The dispersal of shallow, supercooled (colder than 0oC) fog or stratus cloud decks is an
established operational technology. The effects from dispersing supercooled fog and stratus are
easily measured and the results highly predictable. Hence, randomized statistical verification
has generally been considered unnecessary.

Dispensing ice phase seeding agents, such as dry ice, liquid nitrogen, liquid propane, or silver
iodide into supercooled fog and stratus is effective in improving visibility. Clearings established
in cloud decks embedded in strong wind fields fill in quickly, unless seeding is done nearly
continuously. Selection of a suitable technique is dependent upon wind, temperature, and
other factors. Dry ice has commonly been used in airborne delivery systems. Liquid carbon
dioxide, liquid nitrogen, and liquid propane have been used in ground-based delivery systems at
some airports.

The dispersal of warm (warmer than 0oC) fog or stratus decks over areas as large as airport
runways has been operationally applied via introduction of a significant heat source. The mixing
of drier air into shallow fog by helicopter downwash can create localized clearings. Various
hygroscopic (water attracting) substances have also been used to improve visibility in these
situations, but with less satisfactory results than in supercooled fog.

Winter Precipitation Augmentation
The capability to increase precipitation from wintertime orographic cloud systems has been
demonstrated in a number of research experiments. The evolution, growth, and fallout of
seeding-induced (and enhanced) ice particles have been documented in several mountainous
regions of the western United States. Enhanced precipitation rates up to about 1 mm per hour
have been measured in seeded cloud regions. Although conducted over smaller temporal and
spatial scales, research results tend to be consistent with evaluations of randomized

experiments in larger project areas as well as a substantial and growing number of operational
projects. Increases of 5% - 15% in winter season precipitation have been consistently reported
in target areas that are effectively treated by cloud seeding projects, and generally accepted by
the scientific community. Similar results have been found in both continental and coastal
mountain regions. The consistent range of indicated effects in many regions suggests
widespread transferability of the estimated results for supercooled orographic clouds.

Wintertime snowfall augmentation projects can use a combination of aircraft and ground-based
dispersing systems. Although silver iodide compounds are still the most commonly used
glaciogenic (ice forming) seeding agents, dry ice is used in some warmer (but still supercooled)
cloud situations. Liquid propane also shows some promise as a seeding agent when dispensers
can be positioned above the freezing level on the upwind slopes of mountains at locations
sufficiently far upwind to allow growth and fallout of precipitation within the intended target
areas. Dry ice and liquid propane expand the window of opportunity for seeding over that of
silver iodide, since they can produce ice particles at temperatures as warm as -0.5oC. For
effective precipitation augmentation, cloud seeding methods and guidelines need to be
adapted to regional meteorological and topographical characteristics.

Technological advances have aided winter precipitation augmentation projects. Fast-acting
silver iodide ice nuclei, with higher activity at warmer temperatures, have increased the
capability to augment precipitation in shallow orographic cloud systems. Computer models
have been developed to simulate atmospheric transport, as well as meteorological and
microphysical processes involved in cloud seeding; and these models are coming into use in
operations.

Finer scale atmospheric computer models are currently showing skill in predicting
the amount of natural precipitation down to short time intervals such as individual storm
periods. High resolution airborne radar and lidar systems are being used to study the fine scale
structure of air motion and cloud and precipitation particle evolution in the boundary layer over
mountainous terrain. These airborne remote sensing instruments are capable of documenting
changes in cloud structure that may be occurring due to cloud seeding processes, and in the
cloud regions that are the most difficult to observe by in situ aircraft probes or ground-based
radar.

Improvements in computer and communications systems have resulted in a steady
improvement in remotely controlled ground-based silver iodide generators, permitting
improved positioning and reliable operation in remote mountainous locations. Equipment
improvements include solution flow control and atomization technology. There have been
improvements in silver iodide flare rack designs and flare sizes. Also, improvements in weather
prediction and remote meteorological measurement telemetry are advancing capabilities in
weather modification technology.

Traditional statistical methods continue to be used to evaluate both randomized and nonrandomized
wintertime precipitation augmentation projects. Highly accurate quantitative
precipitation prediction, especially for orographic situations, is providing a promising option for

evaluation of cloud seeding experiments. Results from similar seeding projects are also being
pooled objectively to obtain more robust estimates of cloud seeding efficacy. Objective
evaluations of non-randomized operational projects continue to be a difficult challenge. Some
new methods of evaluation using the trace chemical and physical properties of segmented
snow profiles have been used to establish targeting effectiveness and estimate precipitation
augmentation over basin-sized target areas.

Summer Precipitation Augmentation
The capability to augment summer precipitation from convective clouds has been
demonstrated in some project areas, and the scientific community places a lower degree of
confidence in the indicated effects of these efforts compared to that for winter precipitation
augmentation, for a number of reasons, especially their cloud dynamical differences.

Augmentation of summer precipitation normally involves delivery of either hygroscopic
(waterattracting) or glaciogenic (ice-forming) aerosols into the updraft regions at the bases or above
the freezing level of the subject clouds with the intention of modifying the clouds? internal
microphysical structure to enhance the growth of precipitation particles. The modification of
cloud microphysics and precipitation inevitably feeds back to cloud dynamics such that the two
processes combined alter the precipitation further. The outcomes of the seeding depend
strongly on the initial conditions.

Results from research projects conducted on summertime cumulus clouds are encouraging but
somewhat variable. Part of the resulting uncertainty is due to the variety of climatological and
microphysical settings in which experimentation has been conducted. Other important factors
include the spatial scale at which the investigations are conducted and the seeding mode. A
research project that combines the statistical results with microphysical documentation of the
way in which rain enhancement is achieved is still lacking.

Assessments of some operational and research projects that have seeded selected individual
clouds or clusters of clouds with either glaciogenic or hygroscopic nuclei have found that
seeded clouds tend to last longer, expand or travel farther to cover larger areas, and are more
likely to merge with nearby clouds and produce more precipitation. Both dynamic and
microphysical changes appear to be involved.

Most summertime seeding projects have been evaluated using radar data, making it possible
that some of the seeding results have been confounded by seeding-induced changes in the
drop sizes that will in turn affect the radar reflectivities and the inferred rainfall rate. This would
tend to exaggerate the seeding effect. This uncertainty applies especially to hygroscopic cloud
seeding efforts in which the goal is to increase the droplet sizes.

Evaluations of operational summer precipitation augmentation projects present a difficult
problem due to their non-randomized nature and the normally large temporal and spatial
variability present in summertime rainfall. Recognizing these evaluation limitations, various
methods for the evaluation of such projects have been developed and used, ranging in scale
from individual clouds to floating targets of varying sizes to area-wide analyses.

The results of many of these evaluations, at the single cloud scale through floating target areas
up to 2,000 km2, have indicated a positive seeding effect in precipitation. Area-wide effects can be more
difficult to discern due to the large temporal and spatial variability in summertime rainfall
noted earlier. In some instances, apparent positive effects of seeding have also been noted
outside the specific targets. Thus, the apparent effect of seeding is not necessarily confined to
the directly-treated clouds. The physical mechanisms leading to those effects outside the
directly-treated clouds are not yet fully understood.

Technological advances have aided summer precipitation augmentation projects. These
include fast-acting silver iodide ice nuclei, new hygroscopic seeding formulations, polarimetric
radars, satellite-based microphysical observations of the clouds, sophisticated radar and
satellite data processing and analysis capabilities, advancements in airborne cloud physics
instrumentation, and full bin microphysics numerical modeling.

Hail Suppression
The capability to suppress damaging hail continues to improve. Attracted by potentially large
benefit/cost ratios, many countries are conducting projects where hailstorms are seeded to
reduce the damage caused by hail. While there are a number of conceptual models regarding
the formation and mitigation of hail, the most common treatment method for hail suppression
involves the addition of high concentrations of ice nuclei (usually silver iodide smoke particles)
into the new growth regions of storms from aircraft or ground-based sources to manipulate the
hail embryo formation process and thus limit the growth of hailstones.

Evaluations of carefully conducted hail suppression research and operational projects have
shown statistically significant reduction in damage caused by hail to agricultural crops and
property. Studies of long-standing hail suppression operations in a number of locations around
the world indicate a range of effects from 25% to 75% reduction in damage. Advances in radar
data processing and evaluation techniques are helping to provide additional insights into the
effects of cloud seeding. Microphysical measurements from single-cloud studies and radar
analyses are also providing encouraging evidence consistent with the conceptual models of hail
suppression. These technological advances and research efforts continue to develop improved
understanding of hail growth and hail suppression.

The Weather Modification Association does not endorse the use of hail cannons. To date there
is a lack of what the WMA considers to be any scientific evidence that hail cannons produce an
effect on a thunderstorm?s ability to produce hailstones, including the reduction of damaging
hail from those storms. Furthermore, there is no scientifically based expectation that this
method will work.

Status of the Discipline
The fundamental principles and primary cloud treatment strategies involved in weather
modification are reasonably well understood and a substantial body of evidence regarding the
effectiveness of cloud seeding exists. Attainment of desirable weather modification effects
depends upon several factors, including the weather regimes of a specific area and their
meteorological characteristics, the design of a project to achieve a specified goal, and effective
targeting of the seeding agents into the right clouds in space and time.

The "level of evidence" issue regarding weather modification effectiveness remains a topic of
some debate in the scientific community. An increasing number of cloud seeding practitioners,
scientists, sponsors, and investigators accept the growing body of primarily statistical results
along with some objective physical evidence in support of cloud seeding for beneficial effects.
Also there are scientists who are not convinced by the current level of evidence, especially
regarding precipitation enhancement efficacy, and who recommend further research to
demonstrate replication of results. Furthermore, the physical impacts of seeding using
hygroscopic nuclei on precipitation efficiency are less certain than those involving ice nuclei
type seeding. The ranges of effects discussed in this WMA Statement on Weather Modification
Capabilities take into account:
a) the statistically significant results of some carefully
controlled-randomized experiments,
b) the physical evidence obtained through laboratory and
atmospheric experimentation and observation,
c) the ability to replicate the results with cloud
simulations, and
d) the results of less robust statistical evaluations of large numbers of
nonrandomized cloud seeding projects over decades. It remains to those considering application of
cloud seeding technologies to determine what level of evidence is appropriate for their
decision-making.

Persisting challenges in weather modification include determining and defining the conditions
under which predictable and consistent effects may be achieved, and establishing and
executing the most effective cloud treatment strategies. It also appears that, in some
situations, the effects of air pollution, desert dust, and sea salt aerosols on precipitation can
confound estimation of the effectiveness of cloud seeding, such that these effects should be
considered in the design, execution, and evaluation of cloud seeding projects. It is also
important to continue the development and application of methods for estimating the
effectiveness of weather modification projects, especially operations conducted without
randomization. Continued applied research into weather modification issues is encouraged.

Incremental advances in the science and technology of weather modification will lead to
improvements in cloud seeding opportunity recognition, treatment strategies, and methods for
evaluating cloud seeding effectiveness. Such advances will lead toward eventual optimization
and broader acceptance of cloud seeding applications and, thus, fuller realization of the
potential of this technology. In recognition of this the WMA encourages continued objective
investigation of these processes using new instrument and modeling tools as these become
available.

http://weathermod.org/wp-content/uploads/2018/03/Capabilities.pdf