THE United States' financial support of the United Nations Environment Program is shriveling - just as that agency is nearing significant international successes. During the past three years in which the US has cut its contributions to the agency in half, UNEP has been a catalyst for action on global problems that threaten the life support systems on Earth.
Scientists say that some ozone depletion may have already occurred and that global warming from the greenhouse effect may now be observable. This is not the time for the US to withdraw support from the UN's environmental arm.
Once perceived to be the most environmentally responsible nation in the world, the US has a pitiful record of support for UNEP in recent years. Since 1985 the US contribution to UNEP has dropped from $10 million to $6.8 million in 1987 - to $4.8 million proposed for 1988.
Is this lack of financial support linked to a lack of accomplishment or action within UNEP? Hardly.
UNEP's role as an effective leader on global issues was aptly demonstrated in October 1985, when it cosponsored an international scientific conference in Villach, Austria, on climate change and the greenhouse effect - the global warming expected from pollution of the earth's atmosphere.
Characteristically, that conference was a cooperative UNEP effort with two other international agencies concerned with the earth's natural systems, the World Meteorological Organization and the International Council of Scientific Unions. Uncharacteristically, the conference resulted in a statement of rare scientific consensus.
Some 80 scientists from 29 countries concluded that ``as a result of the increasing concentrations of greenhouse gasses, it is now believed that in the first half of the next century, a rise of global mean temperature could occur which is greater than any in man's history.''
Conference participants also departed from traditional reluctance to consider policymaking, observing that ``the rate and degree of future warming could be profoundly affected by governmental policies on energy conservation, use of fossil fuels, and the emission of some greenhouse gases.''
The consensus at Villach clearly demanded further global action. Working with the US Environmental Protection Agency, UNEP cosponsored last June 1986 a week-long conference on depletion of the earth's protective ozone layer and climate change, highlighting the risks of such changes to human health and the environment.
Sixty of the world's top atmospheric scientists and policymakers from nine countries weighed the potential effects of increased ultraviolet radiation from ozone depletion on plants, aquatics, and human health, as well as the effects of a global warming on sea level, water resources, and agriculture.
But the most critical of UNEP's current goals is to achieve a protocol to put in effect the Vienna Convention for the Protection of the Ozone Layer.
The convention, which was put together by UNEP in 1981 and finally signed in 1985, establishes for the first time the framework for a worldwide cooperative pollution control agreement, and one that attempts to anticipate an environmental problem.
But depletion of the ozone layer will not be averted unless concerned parties meet and reach agreement on a protocol - what to do exactly, and how to do it. Organized by UNEP, these negotiations represent important continuing progress in reaching a genuine solution for the ozone layer.
Last month in Geneva, 120 representatives from 25 countries agreed that new measures must be taken soon to control emissions of ozone-depleting chemicals. Despite the European Community's and Japan's reluctance to consider long-term control measures, UNEP is forcing the pace: It has scheduled the second round of negotiations in Vienna for next month.
The issues raised by ozone depletion and the greenhouse effect transcend continental borders. They cannot be solved unilaterally. They demand a forum in which the nations of the world face each other as fellow inhabitants of the planet, to agree on solutions for problems that threaten us all.
UNEP has proved its ability to stimulate leadership on key global resources issues. The US has an obligation to itself and the rest of the world to give UNEP the financial support it needs to continue that work.
Rafe Pomerance is a senior associate at the World Resources Institute, a Washington-based policy research center.