National Science Foundation Staff 2 weather Washington, D. C. moHcallon' Introduction Weather modification, should it some day prove practicable, has the potential to help alleviate many problems. In the past year, for example, large areas of the nation have been devastated by floods and hurricanes. Drought persists in other areas. Polluted air and die need to grow sufficient food to satisfy the world's explosively increasing popula- tion constitute problems that are global in scope. The new nations of the world are eager for tools that will aid in management of natural resources and make possible rapid economic growth. In each of these cases, the possibility of modifying weather offers some hope that the future may be better than the present. During the past decade, scientists have made considerable progress in gaining a better understanding of basic weather processes. In addition, there has been much experimen- tation on changing weather features. Thus, despite man's still scanty knowledge of rain and cloud formation, there has arisen a desire to try to modify the weather for economic and social purposes. The Federal Government has responded vigorously to this heightened interest, as indi- cated by the following activities: —The Interdepartmental Committee for the Atmospheric Sciences, a committee of the Federal Council for Science and Technology, has taken an increasingly active role in weather research affairs, under the chairmanship of J. Herbert Hollomon, the Assistant Secretary of Commerce for Science and Technology. —A number of Federal Agencies, notably the U. S. Weather Bureau, the National Sci- ence Foundation, the National Aeronautics and Space Administration, the Department of the Interior, and the Department of Defense, have stepped up their support of atmos- pheric research. —The National Science Foundation has created a Special Commission on Weather Modification. This commission has been charged with assessing the anticipated benefits to be gained from weather modification efforts, the general paths research and develop- ment should take, the support required, and the legal, social, and political problems that will be encountered if weather modification techniques are more broadly applied. —The Bureau of Reclamation, Department of the Interior, has begun a program whose principal activity will be to test and, where feasible, to apply currently available tech- niques to increase precipitation in mountain watersheds, principally in the Upper Colo- rado Basin. Special impetus was provided to this effort by the Congress, which added to the Fiscal Year 1965 Interior Department appropriation in order to make possible an immediate start. —Committees of both Houses of Congress have begun to look closely into specific Fed- eral weather modification activities, in the light of larger Federal investment in field tests and back-up basic research, and in response to pressures to move more quickly toward applications. 1 Excerpts from the Sixth Annual Report on Weather Modification of the National Science Foundation. The complete report may be obtained from the Government Printing Office, Wash- ington, D. C. 2 Prepared under the direction of Dr. Earl G. Droessler, Head, Section on Atmospheric Sciences, National Science Foundation. 294 Vol. 46No. 6, June 1965 Unauthenticated | Downloaded 09/23/21 09:55 PM UTC Bulletin American Meteorological Society These pressures, it should be noted, usually result from a natural desire to utilize tech- niques already partially developed, such as cloud seeding. However, long-range weather modification is well beyond our current scientific grasp. Such an undertaking may re- quire tools many times more sophisticated and possibly more powerful than those needed when circumstances may permit dispelling a fog or wringing an additional amount of precipitation out of clouds ascending a mountain range. Indeed it is well to make clear the significance of the goal that is sought and which may (no more certain word can yet be used) be within man's reach. This is the ability to alter the weather and the climate in which men live, to diminish the incidence of violent storms, and to change large-scale air circulations in ways that will bring adequate pre- cipitation to areas that are now semi-arid or desert. In brief, it may be possible, with imaginative, long-term effort, to change the face of the earth itself by altering the large- scale features of the weather. This is an undertaking whose rewards to mankind and whose scientific and engineering challenges rank with those of developing peaceful uses of nuclear energy or placing a man on the moon. But weather modification is several steps behind atomic energy and the exploration of space. The scientific principles of nuclear reactors and space travel are well in hand; the problems we now face in these pursuits are—though of high com- plexity—mainly engineering. But the achievement of large-scale weather modification depends upon scientific knowledge we have not acquired, knowledge about atmospheric processes ranging from the interactions of minute water droplets to the behavior of global circulations. The atomic age, now in its third decade, is still without widespread peacetime applica- tions. Space exploration will be well into its second decade before man sets foot on the moon. Such efforts consume the energies of a generation. It is not surprising that the achievement of the full potential of weather modification will probably take a similarly long time. While substantial progress has been made, both in acquiring fundamental knowledge of the atmosphere and in developing engineering applications, the pace has necessarily been slow. If we are to evaluate and exploit the potential of weather modification in our lifetimes in order to help solve problems of resource management and world popula- tion before they become critical, the effort in atmospheric research, both fundamental and applied, must be accelerated. To achieve this acceleration means placing a higher na- tional priority on the goal of weather modification than has yet been done. Among guidelines for such a high-priority effort should be these: 1. It should be recognized that practical applications of weather modification in the broad sense may require an effort of scope and duration comparable to that in nuclear physics research and reactor technology development which led to the development of the peaceful uses of atomic energy (although there is indication that the overall cost may be somewhat less). We are presently in the research phase. 2. Development work and engineering applications of currently available scientific knowledge should be looked upon not only as aims in themselves, but also as monitors of the state of current knowledge and as indicators of directions for future research. 3. An essential ingredient to success is vigorous fundamental research continuing un- abated after application has begun. Operations and research should be regarded as co- essentials, rather than as competitors. 4. Cooperation among Federal agencies, already enlarged by the annual NSF Inter- agency Conference on Weather Modification, by the activities of the Interdepartmental Committee for Atmospheric Sciences, and by other means, should be strengthened. So also should methods of supporting productive research in the universities, where the great bulk of scientific talent resides, and will continue to reside. 5. The most critical problem in an augmented, long-range national effort in atmos- pheric research is the availability of highly skilled research manpower. Many funda- mental scientific and engineering problems of weather modification will be solved by persons who are still in high school or undergraduate study. Emphasis must therefore be given to attracting young scientific talent to atmospheric research and to the strength- ening of university curricula and research in the atmospheric sciences. 6. International cooperation in support of weather modification activities must be in- 295 Unauthenticated | Downloaded 09/23/21 09:55 PM UTC Vol. 46, No. 6., June 1965 creased. First, the world observational network essential for large-scale weather modifica- tion research (as well as for more accurate weather prediction) will require the cooperation of many nations. The World Meteorological Organization has already taken important steps to augment the global network. Second, since large-scale weather or climate control schemes cannot be contained within national boundaries, international cooperation in weather modification experimentation should be consolidated while the problem is still scientific and largely hypothetical in nature. Divergent views on Public Law 510 of the 85th Congress (1958) directs the National Science Foundation to weather modification "initiate and support a program of study, research, and evaluation in the field of weather modification . and to report annually to the President and the Congress thereon." NSF's responsibility is therefore not only to support weather modification research, but to present an overview of the state of knowledge and effort in weather modification. It also promotes the exchange of information about the plans and programs of the various Federal agencies and provides for cooperation at the working level through the annual Interagency Conference on Weather Modification,3 where much of the current Federal interest in weather modification has been kindled. Few recent areas of scientific endeavor have been surrounded by as vigorous contro- versy as has