STATEMENT OF DR. WALTER ORR ROBERTS, DIRECTOR, NATIONAL CENTER FOR ATMOSPHERIC RESEARCH Dr. ROBERTS. Mr. Chairman, referring to your opening remarks, I'm glad to join in the determination, now widely shared, to do something about the weather. Dr. Haworth and Dr. Chamberlain have given you very comprehensive statements, and our time is short to cover the many, many things that I would like to say. Consequently, I have prepared a written statement amplifying quite a few points that I propose to touch on only in summary in my oral satement. Perhaps you will find it appropriate to include my written statement in the record of the hearing. Of course I shall be glad to amplify any points you ask about it either now or at a later time. Senator CANNON. The written statement will be included in the record of the hearing. You may proceed to summarize it, if you wish. (The document referred to follows:) STATEMENT OF WALTER ORR ROBERTS, DIRECTOR, NATIONAL CENTER FOR ATMOSPHERIC RESEARCH Mr. Chairman and members of the committee, my name is Walter Orr Roberts, and I am director of the National Center for Atmospheric Research (NCAR) in Boulder, Colo. As you may know, NCAR is a basic research laboratory in the atmospheric sciences, and is operated under contract with the National Science Foundation by a nonprofit corporation composed of 21 American uraversities, from MIT and Florida State on the east, to the University of Hawai on the west, and from the University of Texas to the University of Alaska The work of our laboratory in many areas of the atmospheric sciences in interesting and important. Though I will be happy to answer any questions you may have about it. I have restricted this written statement to a more general view of the prospects and challenges of atmospheric modification. As an appetui.x. I have attached a brief outline of the work at NCAR most closely related to atr pheric modification of various kinds. You can see that it is a very signalmad part of our program. Specifically, I shall discuss the following general questions: 1. The magnitude of the prospects for practical benefit in applications of atmospheric sciences. This is a field that has, in my opinion, as na hi prve for the benefit of mankind as the peaceful uses of atomic energy, and it is sim to atomie energy in its scientific and technological complexity. Its state, ever, is not too far beyond where atomic energy research was when Haln Mether had observed fisoqon, but practical atomic bombs or working at. powerplants were but an idea and a hope. Perhaps we can be said to be at place in progress analogous to where our atomie scientists were when the atomic pile began to chain react at Stagg Field in Chicago. 2. The need for new concepts in planning and man igement of applied reneg and engineering projects in weather modification. We are beyond the waeila la's ratory scence though much related laboratory science is still needed hive reached a stage where skilled planni!g and management are required to selve complex logistie and scientific planning problems for new pilot opera's ca in the natural environment. [', * is ༈‚༥』 * i he need for new realism about our nation il research objectives if -ben lieved through large w nie weather or climate modificati t be peretured for a long range program in busie research, organ.zei în s that there is a cor state feedback to and from efforts in applied reward, 4. The need for was plantat g to the rense ? e reservoir of highly k Ther next fonts to carry on the work in eoning decades. This thesis 21 1-gorous program of research and education in the universities, 5. Ile Seed to recognize the impacations of where we are The Weather Lfention techologies available today are extremely rudimentary. To E WEATHER MODIFICATION large program in applied research and development in weather modification without an equally vigorous push in basic research will guarantee in advance that we will not attain all-or even most-of the benefits possible. In the words of the song, "You can't have one without the other." Conversely, we must see to it that new advances in research are promptly put to work for the benefit of mankind. Government laboratories, private corporations, and the universities must cooperate effectively, and perhaps more deliberately than in the past, to assure close and productive coupling of basic research advances to practical weather modification goals. THE NECESSITY FOR ACTION It is heartening to me that the Congress should be so deeply interested in the prospects for modifying the atmosphere for the benefit of man. I personally feel a great sense of urgency of getting on with the job with all the determination and wisdom we can muster; for no matter how determined and wise we are, it will be a matter of years or decades before we have come anywhere near close to reaping what now seem to be the probable ultimate benefits. Not only are these ultimate benefits of great value, but there are many potential rewards on the way. Though there are serious gaps in our knowledge of why the atmosphere behaves as it does, we do know enough about its processes to start immediately, for example, on a balanced, long-range national program to help solve one of the Nation's most pressing present problems: a national water shortage. And this will be an ever more pressing future problem, with the need for increased water usage in an expanding world technology and in an exploding world population. I am not an expert on population nor on the relationships between population, food-producing techniques, and the need for arable land; but it doesn't take an expert to see that whatever can reasonably be done to increase the amount of fresh water available for agriculture and industry should be done, in order to head off inevitable problems of the future. Secretary Udall, in a speech before the annual meeting of the American Meteorological Society in Denver last month, spoke of the need to tap "the rivers in the sky." Ten years ago, this would have been Buck Rogers talk. Even today, this is a statement of determination to reach a goal that we still do not know how to reach, for it involves basic knowledge not yet attained and technology we have not yet mastered. Yet, as you run your finger along the cutting edge of the new research, you are compelled to realize that there is promising evidence that we can, even today, tap this atmospheric water reservoir, albeit to a relatively small And we can do it only very degree and under very special circumstances. clumsily and very inefficiently, with yet unreliable, unpredictable, and partially ambiguous results. But we can do it. I use the words clumsy, inefficient, unreliable, unpredictable, and ambiguous not in criticism of current efforts, which are being carried out with considerable ingenuity, devotion, and patience. These words merely describe where we are, in relation to the potential I can see for modification of weather, climate, and the atmosphere. But To describe in another way where we are today, let me say that in my opinion our current knowledge allows us to realize but a small fraction of the ultimate potential in the field of weather modification. Today we talk about the probability of increasing the yield from clouds over a watershed by a few percent. This seems technologically possible from the basic knowledge we now have. we cannot be content with this. Not only is much more than this likely to be possible, but it can be flatly stated that the know-how we have today-the ability to increase rainfall in favorable locations by a few percent-won't solve the really big water resource problems this Nation and the world will face in coming decades. We can and must do more. A glance through the summary volume of the National Academy of Sciences' Report on Weather and Climate Modification makes this clear. The way to major benefits in weather modification is in large part still blocked by major problems, each of which will require years of hard work by teams of the most skilled researchers we can find. Weather modification, moreover, involves far more challenging total prospects than cloud modification to increase precipitation. We must not overlook the possibilities that the large-scale features of the atmosphere-the paths of jet streams, hurricanes, squall lines-may ultimately prove subject to man's deliberate influences. If this sounds even today like Buck Rogers, many of us, myself included, feel that it is an objective more likely to be achieved than the goal, for example, of increasing by 50 percent the water yield of the Upper Colorado River Basin through cloud modification. Even if our sights are set solely on the objectives of increasing the water resources of drought-stricken or normally arid regions, the attack via modification of the large-scale circulation features of the atmosphere may ultimately prove the most promising. Moreover, to weather "modification" let me also add the word "demodification." The dramatic rise of air pollution over the past 20 years has made it clear that the atmospheric sciences must be applied to conserving as well as developing this precious resource. We have experimentally established that it is all too easy to alter the atmosphere significantly by excessive sewerage of gaseous and smoky wastes. And over and beyond their adverse medical, economic, and esthetic effects, these wastes may be having climatic or other largescale weather influences as yet undetected, though perhaps major, because of the still rudimentary state of atmospheric science. The atmosphere is a totally essential resource of mankind. It begins at our feet, and stretches continuously to the farthest star. We live in it, breathe it, are protected from natural space radiation and meteorites by it. It is the only major source of manufacture of fresh water for the earth. An average drop of water distills from the oceans and rides aloft on the winds-on the average but 10 or 15 days before falling to earth as life-giving moisture. Without the atmosphere, our planet would be as barren as the hostile and lifeless surface of the moon, as improbable an abode of intelligent man as the poisonous vapors of Saturn or Jupiter. The problem we face is to conquer the mysteries of our atmosphere, and through knowledge to bring about the mastery of the atmosphere for the benefit of all mankind. We are, I am firmly convinced, dealing with a field that is, as I mentioned above, similar to atomic energy, not only in terms of its ultimate usefulness, but also in terms of its scientific and technological complexity and in terms of the manpower and time required to realize its potential. In cost, weather modification or control techniques may perhaps prove less expensive to develop than techniques for the peaceful use of atomic energy. But they will not be accomplished with the present timid efforts, short-term funding and tentative manpower commitments. If we are to think in terms of ultimate as well as immediate benefits, we will have to think more realistically, not only about the substantial sums of money that must be invested over a period of many years, but in a number of other ways as well. For we are talking about modifying a physical system-the weather-that has global dimensions and is as intricate a system as any that exists in nature. Money begets activity, but only through a comprehensive national program will activity bring the results we seek. PLANNING AND MANAGEMENT We must be more daring and more persevering in our concepts of the planning, management, and logistic requirements involved in basic research, practical experimentation, engineering development, and operations in atmospheric modification. In one of the most impressive sections of its report, the National Academy of Sciences Panel states flatly that "the present fragmentation of effort in weather modification research and development" has led to a situation where "many of the fragments are below critical size or quality needed for effective work." It further states that the present situation doesn't provide proper mechanisms either for setting priorities among large, costly projects, or for planning and managing their scientific and logistic complexities once a project is chosen. We cannot progress adequately until this situation is righted. SOME IMMINENT PROSPECTS The need for a new mode of management and planning becomes clearer if we discuss in some detail the three kinds of weather modification which, in my 1 "Weather and Climate Modification. Problems and Prospects," final report of the Panel on Weather and Climate Modification, NAS-NRC Publication 1350, Washington, D.C., 1966, vol. 1, p. 21. opinion, are among those having the brightest prospects in the next few years. In each of these, the logistics are difficult and expensive. In each of them, developments in engineering and in scientific research will have to be closely coupled, because as engineering advances are made, the need for specific pieces of basic knowledge will achieve critical significance. And progress in each of them will carry with it a whole series of political, economic, and legal questions. Orographic precipitation.-This occurs in regions where a mountain barrier uplifts and thus cools the air flowing across it. It now appears certain that in some mountainous regions, winter snowpack can be increased at least a few percent by seeding of all appropriate winter storms with silver iodide. Having said this, we have said a good deal of all we know today. We know that it happens, and we have some theories to explain why. But there are enormous holes in our knowledge. If we are looking for the best possible design to produce the greatest possible result, we have almost certainly not yet understood the factors that will allow us to specify such a design. Without a doubt, we are thus still in the Model-T era of cloud seeding. We do not yet understand the life cycles of mountain clouds well enough to know the best time and place to insert the silver iodide. We are not yet sure of where to place our generators so that the silver iodide will get to the right part of the cloud, assuming we knew where that was. We do not yet know adequately the abundance of natural seeding nuclei in given cloud systems. The design of seeding generators is still rudimentary and empirical; engineering and research wisdom must be put to this problem. The best generator depends on what size, concentration and character of silver iodide particles you wish to generate, and our knowledge of these winter-storms clouds is not yet sufficient to answer any of these questions with certainty. And so on. At each step of the way, it is necessary to conduct extensive experiments, studies, and tests to see what the results do to our theories about these storms. But we now know what things to tackle first, and this is a great step forward. Hail suppression.—The Russians have already conducted large field programs in their wheat-growing country which is as plagued with hail as are our American High Plains. The Russian hail-suppression system, briefly, is this: They, like us, have an empirical understanding of the kind of cloud that is likely to produce hail. If such a cloud appears, they fire away at it with rockets or artillery shells loaded with silver iodide, or they use plane-borne seeders, on the theory that the silver iodide will induce the formation of many small hailstones rather than a few large ones, and that most of the small hailstones will melt before reaching the ground. They have claimed 100-percent success in some field efforts-that is, during an entire season they say that no hail damage occurred in certain areas where storms with large hail occur many times during a normal season. Similar experiments in other countries have produced less straightforward results. The first step in a U.S. national hail suppression program (and a very sound plan is now being organized), is to try to understand the phenomena involved in hail, and the thunderstorm that produces it. But to probe and understand hailstorms is a gigantic undertaking, requiring not only the talents of many scientists, but also a high degree of organization, backed up by engineering skill and expensive equipment-aircraft, radars, new kinds of measuring devicesall spread over a large area and, if feasible, mobile as well. NCAR, for example, needs a jet airplane to carry thunderstorm-probing "dropsondes" above the crests of hail-producing storms, something a propeller plane cannot do. This scale of operation is not a venture for a single university scientist, or two or three. It requires skilled organization involving dozens of creative scientists and several times that number of technicians to back them up. As I will discuss in further detail later, the scientific talent needed for such undertaking is scattered across the country, mainly in the universities, and it is critically important that our attack on hail suppression be organized in such a way as to use this talent and at the same time not impair the primary goals of these university scientists; namely, to train a new generation of still more numerous and talented scientists. of Air pollution. When we speak of modifying the atmosphere, we often overlook the fact that man is already modifying his atmosphere by spewing into it great amounts of fossil-fuel exhaust and other contaminants. Indeed, we may be touching off processes that will have significant long-range effects on the climate of entire regions. It is essential, before we go through many more years binow dont of this constant increase in pollution, that we understand its full impact on the air we breathe and the climate in which we live. The atmosphere, whether we like this or not, is a complex system. It is, indeed, a great arena in which many processes are simultaneously taking place, each of them interacting and feeding back on other processes. To trace the full cycle of inserting various gases and particles in the air from our industrial and urban centers is thus a fiendishly complex problem, requiring research in the laboratory, extensive measurements in the field, and the applications of advanced mathematical and computer techniques. This is one area in which substantial progress has been made in the last 5 years, under the leadership of the Public Health Service, and with active collaboration from other agencies. It is essential that this progress continue into the more complex and costly stages of applications to come. This brief sampling indicates the size and complexity of the problems that lie in the road to practical benefits. It is also important to note that the idea of weather modification, even in the short run, implies something far broader than increasing precipitation. To view atmospheric modification only as a means of adding to our water supply would be to sell its prospects tragically short. Thus I urge, when you consider what the proper role in weather modification is for the Federal Government and how it should be pursued, that you look at it in an appropriately broad context. THE ROLE OF BASIC RESEARCH Looking to the future, we must also be realistic in our conception of what is needed in weather and weather modification research. The kinds of research we will carry on in the future require the best technological support we can muster. For example, a worldwide observing system now being planned by ESSA-the world weather watch-will make it possible for the first time for us to describe the atmosphere as the global entity it actually is (for, as you know, storm systems are linked and interact on one another all the way around the globe). This observing system will probably require two artificial satellites, thousands of free-floating weather balloons of a remarkable new type that NCAR is now experimenting on, and other remote sensing devices to bring the nowunobserved 80 percent of earth under adequate weather observation. But this is not the only requirement for effective long-term progress in both weather prediction and weather modification. Another is vastly enlarged computing capabilities. We must have computers with 100 times the speed and capacity of the largest computer available today, and we need to have its intricate computing programs written in such a way as to exploit the most advanced knowledge of how the wind and weather systems behave. Both are today in sight. And with both in operation we will be in a very favorable position to do weather modification experiments-in a computer-with very exciting potential consequences. Let's consider for a moment some of the possible large-scale weather modification schemes that have been suggested in recent years by various scientists. The late Harry Wexler, distinguished chief scientist of the Weather Bureau, suggested that if lampblack were spread on the polar icecap, it might change the radiative balance in polar regions and thus warm the surface, increase the melting of ice, and through this affect the delicate ice versus water equilibrium of the Arctic Sea. This, in turn, one can speculate, might well result in a more frequent occurrence of the kinds of outbreak of polar air that trigger winter cold waves and blizzards in temperate latitudes and also bring spring rains to promote crop growth. Another scheme proposed several years ago was to build a dam across the Bering Strait between Alaska and Siberia, in order to regulate the flow of cold Arctic waters into the warmer North Pacific, and ultimately through temperature effects to modify the evaporation, temperature, and winds in that region. The original proposal, advanced by the U.S.S.R., was designed to lengthen the growing seasons of eastern Siberia and western Canada, and thus to increase wheat production in both Canada and the U.S.S.R. A more modest idea, of which I was the author, speculated about the possibility of creating layers of artificial cirrus clouds (not unlike those that sometimes form on jet airplane contrails) over the Gulf of Alaska, which might act as atmospheric "blankets" at a critical altitude and thus pump heat into the wind systems. The effect might be to deepen winter storm systems and divert them further south. A storm that would otherwise travel eastward along the |