Taking a new look at how Earth works. The International Geo-Biosphere Project would employ top scientists and best technology to unravel the globe's environmental mysteries

EVEN before acid rain was ``hot,'' Irving Katzenstein, an industry lobbyist, hauled out reams of documents as proof that the latest environmental threat wasn't all it was cracked up to be. ``Overblown,'' he said. Michael Oppenheimer, an environmental lobbyist, apparently dug up different material. His acid rain assessment: ``Catastrophic.''

The ensuing debate has engulfed hundreds of scientists, resulted in a lobbying frenzy from all sides, and stalled a Congress groping for a way to deal with an environmental problem clamoring for solution.

It has also dramatized the kind of bind in which politicians find themselves with increasing frequency: being expected to take decisive and controversial legislative action based on scientific guesswork. Acid rain, experts say, is part of a new wave of environmental assaults -- including ground-water pollution, topsoil depletion, and carbon-dioxide buildup -- in which links between cause and effect are fuzzy. William Ruckelshaus, former administrator of the Environmental Protection Agency, said recently: ``They are the harbingers of things to come.''

They are also cropping up as man begins to disrupt Earth's environment on a planetary scale. At the same time, a spotty understanding about the workings of the global system as a whole often prevents scientists from responding with more than educated hunches.

Quietly, however, enthusiasm is building among scientists for an international project aimed at filling many of the gaps in knowledge. The inquiry would be of unprecedented magnitude. Studies of the global climate, as well as geologic processes beneath the Earth's crust, would be included. It would strive to better understand the sun's cycles, as well as the biogeochemical cycles of nutrients critical to the global life-support system known as the biosphere.

As its architects envision it, the project would reap data from satellites in orbit, instruments on the ground, and researchers in virtually every region of the world. It would involve scores of countries and thousands of scientists. And it would do so for decades.

The political and economic obstacles to such an undertaking are said to be enormous. Questions of scope, duration, and financing also loom ahead. Yet momentum for the International Geo-Biosphere Project, as the program is called, is undeniably growing. At the present rate of activity, project backers say, the IGBP could be a reality by 1986.

At its September biennial meeting in Ottawa, the International Council of Scientific Unions (ICSU) vigorously endorsed a two-year study to draft a multinational game plan for implementing the IGBP. This week, after a seven-month effort, a committee of the US National Academy of Sciences (NAS) submitted to the academy's governing board for approval a set of sharply focused initiatives for the program.

The Soviet bloc, critical to the success of such an undertaking, seems to have taken early interest in the project. The Soviet Ministry of Environment, along with Vienna's International Institute of Applied Systems Analysis, are sponsoring a biosphere conference in March. IGBP organizers have even noted a receptive US Congress: Three days of hearings were held on the topic by the House Committee on Science and Technology last year; more will be scheduled after the NAS initiatives are published sometime in March.

``It's all taking on certain inevitability -- we've gone beyond the wishful-thinking stage,'' says Herbert Friedman, an NAS official and originator of the IGBP idea. ``Everywhere I go people are excited about this.''

THIS would not be the first big international scientific collaboration. The IGBP was at first envisioned by some as a way to commemorate the 25th anniversary of the International Geophysical Year (IGY) of 1957-58. Back then, observations gathered from pole to pole by the scientists of 67 nations not only contributed to an understanding of the physics of the Earth, but also established the foundation for similar programs and a basis for international cooperation in research generally, officials say.

``The Geophysical Year set the pace for two decades of science,'' says Dr. Friedman. ``We all thought that instead of just observing the International Geophysical Year's 25th anniversary, it would be much more appropriate to see what we could accomplish with all the technical advances we've made since then.''

Yet from its inception, the IGBP attracted powerful support in its own right, because many scientists found the idea so compelling. They say that issues like acid rain and atmospheric problems such as carbon-dioxide buildup or the possible depletion of Earth's precious ozone layer have highlighted the need for a comprehensive approach to global problems -- one built on an understanding of how the myriad fragments of the ecosystem interact with one another. They also note that many global processes would have to be studied for decades or even centuries, and that a full-scale IGBP might return its most interesting results after 20 or 30 years.

And since the great environmental problems of the day are not neatly defined within such disciplines as physics and chemistry, or even the categories of earth, water, and sky, this kind of approach would require an interdisciplinary effort of historic proportions. So the IGBP is intended to cut across the barriers of research that have traditionally segregated studies of Earth's atmosphere, oceans, and geology and try to analyze problems from a broader framework. The project would stress biology and chemistry, particularly the biogeochemical cycles of such critical nutrients as carbon, nitrogen, phosphorous, and sulfur. From this, organizers hope, the now-obscured picture of many ecological systems will begin to emerge.

``There isn't an environmental issue that wouldn't benefit from this kind of approach,'' says John Eddy, a meteorologist at the National Center for Atmospheric Research in Boulder, Colo., and chairman of the NAS committee. But in the interests of practicality, he adds, IGBP would limit the scope of its investigations to several of the most intractable environmental challenges the planet faces.

As an example, Dr. Eddy cites the problem of atmospheric buildup of carbon dioxide (CO2), the gas that plants breathe and animals exhale. The industrial age has thrown a kink into that nicely balanced equation -- the carbon emitted from burning fossil fuels reacts with oxygen in the atmosphere to form more CO2. How much more? Nobody knows for sure.

The answer is important because CO2, along with other so-called greenhouse gases, acts as a thermal blanket, keeping the warmth of the sun's radiation from escaping into space. If that blanket becomes too ``thick'' -- if the greenhouse-gas concentration becomes too high -- atmospheric temperatures may rise and have profound effects on Earth's climate.

SOME research indicates that temperatures around the world have gone up half a degree in the last decade because of greenhouse warming. At current rates they could rise another 10 degrees in the next century, changing climate patterns, shrinking polar ice caps, and raising world water levels. The scenario raises many questions for scientists.

Will rising CO2 levels stimulate plant growth and increase the biosphere's ability to absorb the gas? (A question for biologists.) Or will the declining ability of the oceans to absorb CO2, which occurs with increasing temperature, negate that effect? (A question for chemists.) And for that matter, do carbon particles from fossil-fuel-burning factories remain in the air long enough to form lots of extra CO2? (A question for atmospheric scientists.)

Answers to these questions could have far-reaching policy effects. For instance, if fossil fuels do turn out to be the cause of a global warming trend, an eventual ban on the burning of coal and oil may be required.

Methane, also a greenhouse gas, presents yet another puzzle. A natural product of bacterial fermentation in waterlogged places like rice fields and swamps and in the digestive tracts in some animals, methane is a trace gas in the atmosphere, with a concentration of about two parts per million. During the last decade its concentration has, comparatively speaking, soared -- roughly 1 to 2 percent a year. No one can say why.

The increase needs to be understood because of the global temperature change it may hasten. Methane is influential in smog formation as well as in the creation of ozone -- a critical gas that helps shade Earth's surface from much of the sun's ultraviolet rays.

History would also play a big role in IGBP. Controversy over the rate of increase of gases like CO2 stems partly from an uncertainty over what CO2 levels were 10,000 or 100,000 years ago. For clues, organizers would step up glacial samplings to study the composition of ice from that era.

Similar efforts to chart historical trends would be made in all the subjects that the IGBP tackles, Eddy says. Efforts to analyze acid rain, for example, have been partly stymied by a lack of historical data showing how the composition of rainfall has altered over time. One IGBP program might include a large-scale effort to sample rain water in so-called pristine areas as a way of studying what conditions may have been like before the industrial age.

SUPPORTERS of the IGBP working with the NAS proposal are confident that they can carry out such without derailing ongoing scientific projects. In fact, they say the means to execute an IGBP are already in place. Existing efforts scattered around the globe have long been probing bits and pieces of issues that the IGBP would hope to swallow whole. So the IGBP might actually end up as a kind of administrative traffic cop, directing and channeling existing activities.

The IGBP would be aided greatly by advances in remote sensing and the rapid development of powerful computers. The technologies provide the ability to collect and analyze the vast amounts of data such a project would bring.

For example, only in the last decade have satellites been able to provide sweeping views of Earth's surface from space. The National Aeronautics and Space Administration (NASA) in 1972 initiated its Landsat series, a succession of satellites that pioneered geological surveys and crop monitoring from space. Data from the National Oceanic and Atmospheric Administration's polar-orbiting weather satellite are being used to compile a weekly ``vegetation index'' map, which charts the sweep of seasonal changes across the continents.

And there are plans for more orbiting observation posts that could be important for the IGBP. In the next few years, Europe and Japan plan to launch satellites similar to Landsat. Other proposed US satellites will chart currents in the oceans and atmosphere. One of them will be a followup to NASA's Seasat, which measured winds and waves over the world's oceans in 1978, and is scheduled begin probing ocean currents in the mid-'80s. At the same time, an environmental observation mission on the US space shuttle will study the chemistry and physics at the fringes of Earth's atmosphere. NASA officials say that a permanent space station, proposed by the agency for the early '90s, will prove central to an effort such as the IGBP.

The planned assortment of satellites lends itself so nicely to an IGBP-style effort that NASA had already planned its own project. Two years ago NASA launched an independent, but very similar, ``global habitability'' program. The idea was to take a look at Earth's ability to support life, primarily its biogeochemical cycles and climate.

``We just thought it was time something like that was tackled,'' recalls former NASA administrator Hans Mark, now chancellor of the University of Texas, who helped come up with the idea in 1982. The global habitability plan, its author's say, was also an attempt to bring coherence and focus to the agency's Earth observations program at a time when it needed a defense from Reagan administration budget cuts.

Few outside the agency shared the enthusiasm for the plan, however. In August 1982, NASA administrator James M. Beggs presented the new idea to UNISPACE, the United Nations space conference, in Vienna. Apparently the message got garbled. A venerable British scientific journal erroneously reported that NASA was proposing a self-sufficient colony on the ocean floor and solemnly pronounced it a good idea.

But many better-informed members of the international scientific community were set against the plan, concerned that it would grab the initiative from existing programs that had taken years to get started. Even at home, global habitability was seen by some as a ruse to grab turf away from other agencies.

NASA put the proposal on the back burner. It never quite disappeared, though. It had found champions in Congress, among the few policymakers who had heard of it. And NASA kept quietly plugging the proposal as an interagency effort.

So, even when the IGBP idea came along, usurping global habitability, ``we were behind it from the beginning,'' says NASA assistant administrator James Watson. ``The IGBP really seemed like the way to go.''

Apparently, the feeling is mutual. The NAS committee's proposal, its authors say, will essentially be a recreation of NASA's once-maligned proposition.

In the early stages of the NAS committee's deliberation, an early rift developed between its members. Some thought the IGBP should cleave closely to the guidelines established in the stalled global habitability proposal. Others felt the IGBP should forge ahead into analyzing some of the more obscure processes that effect the Earth in arcane yet profound ways -- for example, how ocean chemistry, on a million-year time scale, is dominated by hydrothermal action at the midocean ridges. The explanation of just how it is affected, it seems, will have to wait for another day. IGBP, its architects promise, would be eminently practical at heart.

``We want the project to focus on the most pressing enviromental problems,'' says Eddy. ``Our intent was not to string together the 50 neatest projects we could think of and charge ahead.''

Specifics for executing the project have yet to be established. If the two-year sequence of ICSU-sponsored workshops -- such as that of the NAS -- on the geobiosphere project is successful, a multinational game plan for the program will take shape. If that plan is approved by the next ICSU general meeting in 1986, an international coordinating committee will be formed, and the IGBP will be on its way.

By that time, organizers hope many of the wrinkles often accompanying collaborative international programs would have been ironed out. For instance, a staggering amount of data would come pouring in from a project as vast as the IGBP. Without an international data archive using the most advanced technology available, the whole operation would quickly sink. Who will manage the data bank, and where will it be located?

The question is not as picayune as it may sound. Few countries hide weather data; many balk at revealing information about mineral deposits and crop yields. If the IGBP is perceived as a front for military or economic intelligence, it may have serious problems. Organizers says the handling and siting of the data base are critical to the project's success.

SO is cooperation. NCAR's Eddy recalls that recent attempts to chart something as innocuous as the state of worldwide rain forests ran into opposition from countries such as Brazil, which were sensitive to charges that they had handled their natural resources irresponsibly.

Nevertheless, IGBP officials expect that most countries will want to sign on. The project would provide many third-world countries with an entrance into the world of international science which they might not otherwise have. Also, Friedman of NAS points out that many activities critical to the IGBP could be carried out at low cost. Precise measurements of sea level, for example, would have to be taken on a consistent basis over time. The same would go for rain sampling. ``How much is that going to cost?'' he asks rhetorically.

Actually, the IGBP's final price tag is still in the air. But Eddy says it would be comparatively low because a large part of the program's activity would come from the coordination of ongoing investigations. Equally important, it would not run roughshod over those existing programs. ``We're not looking to snatch up every able-bodied scientist,'' Eddy says.

Even so, other questions will inevitably arise, and NAS officials involved with the planning of geobiosphere say they have no illusions about the kind of task before them. Other national committees working on the same problems may have different conceptions of what the IGBP will accomplish. All that will have to be sorted out at the next ICSU conference.

Many US scientists expect the NAS proposal to dominate nevertheless. ``The United States has to take the lead,'' says Eddy. ``Someone has to, and we're the only country with the capability to do so.''

Still, precedent implies that the orchestration of such an effort won't be easy. The Global Atmospheric Research Project, for example, was proposed by President Kennedy in 1961, but the first experiment did not get under way until 1978. And in a project with the ambitions of the IGBP, organizers stress the necessity of maintaining a constant effort over the long haul. Ultimately they say, the program's future will hinge not so much on scientific determination as political resolve.