How Cloudy a Forecast?

THANKS to the three hottest summers on record during the last decade, the American news media has firmly implanted in our collective consciences the idea of the "greenhouse effect." Nearly every week, new evidence and opinions concerning global warming from authorities in science, industry or the government make national headlines.

However, the media has often inaccurately represented the state of the science behind the problem. Moreover, its focus on the alleged debate and dissent within the scientific community has led to two crucial problems: a chaotic message to the public and a stagnation in public policy.

THE TERM "greenhouse effect" is used to represent the accumulation of trace gases in the atmosphere. These gases prevent the release of the sun's radiation back into space and trap the heat in the earth's atmosphere, leading to global warming. Without greenhouse gases like water vapor and carbon dioxide, our planet would reach a much lower average temperature and would be unable to support life as we know it.

Yet with the dramatic increase in recent years in the release of trace gases, such as chlorofluorocarbons (CFCs), methane, nitrogen oxides and especially carbon dioxide, from industrial sources, the atmosphere is undergoing strains possibly never before experienced in its history.

Such information represents the undisputed part of the science so far. Of course, the summary presented above leaves out a great deal of evidence and oversimplifies many ideas pertinent to the conclusions.

According to the most conservative of atmospheric models, our gaseous waste products may lead to an average rise of global temperature by 1 to 4 degrees Celsius during the next 50 to 100 years. Other models are in place in the United States, Great Britain, and Japan, each of which is overseen by a group of scientists working daily to reduce this uncertainty.

There are fewer than 300 climatologists in this country, only some of whom concern themselves with global warming and computer modeling. Each scientist in the field has his or her own estimate as to the extent of the change in the future. All of them, however, agree that the unprecedented global experiment we have created is highly dangerous.

MOST scientific research is quiet, slow, undramatic and lends to poor copy. But when science enters the realm of predicting the future, it opens a Pandora's box full of skeptics, detractors and critics. Journalists gather to report the conflicts or, in the case of the greenhouse effect, create them.

The media, often seeking to find the other side to what they perceive as a two-sided story, has consistently sought quotes from scientists in related fields like meteorology. Citing problems with the current models like incorporating clouds, oceans, and plants into the equations, these supposed experts say that there is enormous uncertainty in the predictions and that are therefore unduly pessimistic.

Yet these critics have virtually no experience in analyzing the relevant data and are merely giving their opinions without supporting data. On the other hand, modelers can cite their evidence in the literature, evidence that is reviewed by scientists in their field. To give equal weight to the opinions of both groups, as the media does, is irresponsible.

BUT THE problem with the media's misportrayal is twofold. First, it suggests an apparent controversy among scientists that by and large does not exist. Second, and perhaps more importantly, the media fails in its responsibility to inform the public clearly on an issue vital to everyone's concern.

After all, it is not the global temperature change itself that matters but the repercussions of that change. These include the raising of sea level due to the expansion of warmer water, more frequent large tropical storms like Hurricane Gilbert, movement of agriculturally productive areas from the tropics to the poles, loss of habitats for plants and animals and growing numbers of environmental refugees.

Such coverage, by giving the appearance of debate within the scientific community and ignoring the likely effects of global warming, has created widespread confusion on the issue and led to a public policy that is counterproductive and even dangerous. For White House Chief of Staff John Sununu insists that we should focus solely on research until we can understand the science better.

Instead, we must continue doing research while, at the same time, begin preparing for a possibly catastrophic future. There's absolutely nothing wrong with an insurance policy against such major economic and ecological disasters. After all, if we pay a little now to develop alternative energy sources or recycle papers and metals, we are sure to save a lot later.

There is a story about cooking a frog. If you put a frog into a pot of boiling water, it will jump right out and you will have no dinner. If you put it into a pot of cold water and slowly heat it, the frog will pay dearly. We have the power to adjust the temperature of our own planet. Let's do it wisely.