Science at Threshold of Global Ecology Research

Sophisticated remote sensing devices in space, coupled with super computers that can process staggering amounts of information, have made it possible for scientists to plan a project that is so ambitious and so complex that it would have been out of reach just a few years ago.

The technology should be available within the next few years to permit scientists from a wide range of disciplines to study the Earth as a single ecosystem, increasing the odds that the planet will continue to support life in the future.

They would like to know the answers to questions that have profound implications for planet Earth. Is the human race upsetting the atmospheric balance through burning of fossil fuels, possibly leading to a warming trend that could have a devastating impact on wide regions of Earth?

What are the causes of acid rain, which is damaging some of the world’s most important forests and respects no international boundaries?

These are two of many scientific enigmas that are global in scope and have defied efforts to resolve them on a piecemeal basis.

What is needed, according to scientists in nearly all disciplines, is an international, global search for the answers.

“We are just getting to the point where this is possible,” said Shelby Tilford, director of earth science and application for the National Aeronautics and Space Administration and a key player in a scientific drama that is slowly unfolding across the country.

Tilford is one of about 30 scientists who met last week at NASA’s Jet Propulsion Laboratory in Pasadena to map out the strategy for an international, interdisciplinary “mission to planet Earth.”

Tilford is NASA’s senior representative on the Earth System Sciences Committee, which was set up two years ago by the space agency under a congressional mandate to determine the feasi bility of a major effort to study Earth as a single system. Other key agencies involved are the National Oceanic and Atmospheric Administration and the National Science Foundation.

The committee, which is scheduled to submit its final report in one year, is expected to recommend a multibillion-dollar, long-term effort that could be without precedent in terms of complexity, both technologically and politically.

At issue is the survivability of a planet that is being constantly modified by “the grand experiment” of the human race, according to Francis Bretherton, chairman of the committee.

Earth as a life-support system is so complex and has been changed so dramatically by human impact that “we may be pushing up against the boundaries” of what makes life possible, said Bretherton, an oceanographer and meteorologist with the National Center for Atmospheric Research in Boulder, Colo. “But we don’t know where those boundaries are.”

Earth as a life-support system should be viewed as a single unit because seemingly unrelated events on opposite sides of the planet can be so interrelated that they have a profound impact on other seemingly unrelated, distant events.

The classic example is weather and its many components, including the effect of the oceans on atmospheric conditions and the changing composition of the atmosphere itself because of human habitation.

Difficulties to Overcome

Scientists have long debated the practicality of a coordinated effort to find the “boundaries” that make life possible, but there is a growing consensus that now, for the first time, it might be possible. The obstacles, as many scientists indicated during the meeting at JPL, are immense, however. Among them:

- There is no single agency in the federal government that has responsibility for such an effort. Like the scientific disciplines themselves, the responsibility is scattered among numerous agencies, and there is great fear that without a single coordinating agency the effort will fail.

- The effort would have to be international in scope. Many countries that have been reluctant to do so in the past would have to open their borders to scientists who could conduct research on the ground in concert with remote sensors in space.

- Such an ambitious program would produce scientific data in quantities far greater than even the most sophisticated computers today can handle. Insufficient management of the data would mean that most of the results would end up in warehouses, unmanageable and unusable.

Tomorrow’s generation of super computers could make it technologically possible, but far less ambitious efforts have failed in the past because even when the technology was available, the financial resources, the know-how, and in some cases the will, was not.

- The project would be very expensive. Data management alone is expected to cost at least $50 million a year, according to Bretherton, and NASA has proposed a series of instruments for an orbiting platform that would cost well over $1 billion.

Picking Up Momentum

All of that aside, however, the effort is gaining momentum and it seems almost certain that “global habitability,” as the project has been called, will be a major issue in the years ahead.

“This is not just a hot issue for this year,” said Bretherton, the committee’s chairman. “This is definitely a long-term effort.”

To be successful, many scientists emphasized during the meeting at JPL, the effort will have to consist of a carefully coordinated study involving many disciplines and many countries. As proof of that, they repeatedly cited the growing amount of carbon dioxide in the Earth’s atmosphere, the so-called greenhouse effect.

The amount of carbon dioxide in the atmosphere has increased dramatically, primarily because of the burning of fossil fuels. Carbon dioxide traps solar radiation within the Earth’s atmosphere, causing the temperature to rise.

John A. Dutton, professor of meteorology at Pennsylvania State University and a member of the committee, said that doubling the present level of carbon dioxide could raise global temperatures “a few degrees, and if you do that you are going to get a significant melting of ice in polar regions. That would raise the sea level, having quite an impact on coastal cities.”

Much of the information needed to study such problems can be obtained by remote sensors aboard satellites or the proposed space station, but the sensors provide only raw data that must be interpreted, and that can only be done with studies conducted on the ground.

And although remote sensors provide massive data on a global scale, the information is difficult to decipher and the volume is overwhelming.

Bretherton said the amount of data relayed to Earth from the kind of sensors envisioned for the program would be greater in a single 24-hour period than the largest computer in the world today can handle.

Faster Computers

The new generation of computers now being developed will be much faster and have a far greater capacity, but speed and capacity are not the only problems.

What is needed will be some sort of breakthrough in artificial intelligence--computers that can not only receive data but also can make decisions and analyze information--and that is a problem that is proving more difficult than many experts had thought.

Even then, the problem of making the raw material available to scientists around the world will be extremely difficult.