HENRY LANSFORD

Last February, after signing a bill establishing a state-supported emergency cloud-seeding program to get more snow in the Colorado Rockies during the remainder of the disastrous "Winter of '77," Governor Richard Lamm referred to the effort as "a roll of the dice."

The atmospheric scientists who had advised the Governor to support the project viewed it somewhat more positively, as a sort of technological act of faith based on scientific evidence that cloud seeding had produced additional snowfall in earlier weather-modification research programs.

Opponents of the cloud seeding saw it as an unwise expenditure of public funds on a scientifically questionable and environmentally reckless venture that might distract public attention from the need for water conservation and other responses to the drought that was afflicting the state.

The buck stopped on Dick Lamm's desk as far as last winter's cloud seeding was concerned, and I'm not here today to try to second-guess his decision to support the project. But I think it's very important to keep several facts in mind about short-term operational cloud-seeding projects such as this one.

First, when such a project is concluded, there is no way to measure with scientific certainty how much additional precipitation was actually produced by the cloud seeding.

Second, most of the scientific evidence for the efficacy of cloud seeding in augmenting precipitation is statistical rather than physical. That is, it says that in field experiments, more precipitation fell from a large number of seeded clouds than from a large number of unseeded clouds, but it doesn't tell us exactly what happened inside individual clouds.

Third, even if the most optimistic scientific estimates of its effectiveness are accepted, cloud seeding is no panacea for a severe and widespread drought like the one that currently is afflicting much of the western United States.

If these caveats are accepted, a cloud-seeding program may be a perfectly rational response to a drought emergency, as long as it is regarded as one tool in a comprehensive program of drought response rather than as a miraculous technological fix for drought. I believe that the Colorado General Assembly acted in this spirit when, along with legislation establishing a number of other drought-related programs, it passed House Bill 1722, which established a state-supported cloud-seeding program to be conducted in the mountains this winter. This bill provides $300,000 from the state general fund, with the stipulation that every state dollar must be matched by fifty cents from other sources such as municipalities or water conservation districts. Cloud seeding is expected to begin around November 1.

So the state's decision makers either have faith in the evidence that cloud seeding can stimulate more snowfall or they regard the drought as a serious enough emergency to warrant a little crap shooting. In deciding to support cloud seeding, they acted on the advice of atmospheric scientists who regarded evidence from previous weather-modification research projects as convincing.

But what about the public--the people of Colorado who are affected by the drought and who will pay the bill for the cloud-seeding project? Does it matter what they think about cloud seeding, and is their any way for them to express their opinions?

I believe that there's no doubt that the ultimate decisions about the operational use of weather-modification technology will be made by the public rather than by politicians or scientists. I am not alone in this opinion--consider this statement from a report published in 1971 by the federal Interdepartmental Committee on Atmospheric Sciences:

What the public thinks about weather modification, rather than what the scientists know about it, will play the dominant role in the future of this science. The most expertly developed technology, whether it is for augmenting water or for suppressing damaging weather phenomena, will find only limited application in the absence of a string public demand.

Recent history provides a number of examples of weather-modification efforts that have been terminated because of public opposition. Only last year, an extensive state-supported weather-modification program in South Dakota died when the state legislature, influenced by public controversy and opposition that had developed, decided not to appropriate funds to continue the program. In Colorado, a private cloud-seeding operation supported by Moravian barley growers in the San Luis Valley was denied a state weather-modification permit because a large number of residents of the valley opposed the program.

I have a number of reasons for believing that the public will make the final decisions about the operational use of cloud seeding in Colorado. One of them is very simple. During almost any six-month period that you want to choose, something unusual will happen as far as Colorado's weather is concerned. Last summer, when no cloud seeding was being done, we had the Big Thompson flood. Last winter, when clouds were being seeded in the mountains, we had a period of extremely high wind that brought severe blizzard conditions to the plains. Although the scientists say that there's no way that the seeding in the mountains could have caused the blizzard on the plains, some people are convinced that it did.

My point is this: if cloud seeding is being done when unusual bad weather occurs, some people will insist that the cloud seeding caused the bad weather. When this happens, there is a good chance that the situation will escalate into a loud and bitter public controversy. And when that happens, the large majority of the public that has had no strong opinion about cloud seeding may be forced to make up its collective mind. By then, it will be very difficult for the scientists and decision makers to explain their decision to seed clouds, because they will be on the defensive. If a good many people who aren't committed to either side of the controversy don't have some understanding of how cloud seeding works and why the decision was made to use it, then the project is likely to be in deep trouble.

In some cases, I believe that public opposition to weather-modification programs has developed for the wrong reasons. It would be a serious mistake to reject cloud seeding simply because most people don't understand what it's all about. On the other hand, I believe that it would be an equally serious mistake to continue a cloud-seeding program that does not have at least tacit support from the people who are paying the bill--Colorado's taxpayers, in the case of the state-sponsored program.

However, to support the program intelligently, the people need to know a good deal about it, including the risks and uncertainties that are involved as well as the potential benefits. It is the responsibility of the scientists, technologists and managers who are running the program, as well as the people in the mass communication media who are reporting on it, to do their best to inform the public accurately and completely about cloud seeding, and particularly about the current state-supported cloud seeding.

If cloud seeding were a sure thing--that is, if the seeders could guarantee that a certain number of dollars invested in a cloud-seeding program would produce so many inches of extra snow over a particular area--then the decision would be pretty straightforward. But instead, the taxpayers are being asked to risk their dollars on a proposition that involves considerable uncertainty but that could provide significant benefits as long as the region is afflicted by drought.

How good is the evidence that, under certain conditions, cloud seeding can produce additional precipitation from mountain snowstorms? According to some sources, it's pretty good. The U.S. Bureau of Reclamation has just released the results of two years of detailed analytical studies of five winter cloud-seeding research projects in the Rocky Mountains and the Sierra Nevada. The study considered four general types of snow clouds that differed from one another in terms of temperature, water content, turbulence and wind conditions. The analysis indicated increases in snowfall ranging from 18 to 52 percent from seeding three types of clouds, and deceases of 54 percent from the fourth type. However, the study didn't establish how frequently each cloud type occurs in various mountain ranges or how much water each type actually contributes to the spring and summer runoff from the melting snowpack.

Regardless of how much faith you have in the credibility of these research results, applying them to operational cloud-seeding programs still involves some gambling. As the ability to get more snowfall by cloud seeding clearly depends on the presence of certain kinds of clouds that are susceptible to seeding, the processes that determine whether or not the right clouds will be present still have to be regarded as a "roll of the dice" in terms of present scientific knowledge.

Assuming that you, a citizen of the State of Colorado, have decided whether you are for or against state-supported clod seeding, what opportunities exist for you to participate in the decision-making process? As far as your elected representatives are concerned, this year's program is already an accomplished fact. If you want to lobby for or against cloud seeding, you should be looking ahead to future legislation that may be proposed.

However, there will be opportunities for public input into this year's cloud-seeding project. Under the Colorado Weather Modification Act of 1972, anyone who plans to try to modify the weather within the boundaries of the state must obtain a license and permit from the Colorado Department of Natural Resources. Before the permit is granted, public hearings will be held in the area where the cloud-seeding work is to be done. Anyone who wantes to testify for or against the permit will have an opportunity to do so at the hearing, and the testimony will be considered by the hearing officer and the executive director of the Colorado Department of Natural Resources before the permit is granted.

I'm sure that in this audience there are some who consider cloud seeding inexcusable tampering with the natural environment and others who would maintain that it is a rational application of scientific knowledge to obtain benefits for humanity. Some believe the evidence is adequate to support faith in cloud seeding for snowpack augmentation as a usable technology that is ready for widespread application, while others see it as nothing more than a roll of the dice.

Personally, I'm unable to find any really compelling evidence that either extreme view is absolutely valid. But I am convinced that the people of the state, rather than the scientists or the politicians, will decide about operational cloud seeding in Colorado. And I am confident that, given complete and accurate information to use in making up their minds, the people are quite capable of making wise decisions.

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