A science adviser to President Bush favors going slow, but other scientists at an international conference on atmospheric changes say that damage already done to Earth's air tells them it's time for action.
"We are not facing a crisis now . . . we have the time to invest" in further research, D. Allen Bromley, a bow-tied nuclear physicist who serves as the president's adviser on science and technology, said this week.
But Valentin A. Koptyug, vice president of the Soviet Academy of Sciences, said, "It is better to be roughly right, now, than precisely right too late."
All parties to the debate are calling for more research into the depletion of the planet's ozone shield and global climate change caused by human activity. They also favor increased cooperation among nations, multi-national corporations and universities to address the problems.
The debate is on at the Chemrawn VII conference in Baltimore, a week-long meeting of 180 scientists from 43 countries sponsored by the International Union of Pure and Applied Chemistry and the American Chemical Society.
Daniel L. Albritton, director of the National Oceanographic and Atmospheric Administration's Aeronomy Laboratory, said hard data reveal a 25 percent increase in atmospheric carbon dioxide in the past 150 years, a doubling of methane, and a quadrupling of other greenhouse gases since the 1950s.
If such trends continue, he said, "based on our current understandings . . . some degree of global warming will eventually occur."
These changes are long-lived and irreversible within a human lifetime, Albritton said. In that light, "some action soon is easier than any action later."
BTC Elwood P. Blanchard agreed. He is vice chairman of the DuPont Corp., which saw the ozone depletion data in 1988 and agreed to stop making CFCs by 1994 and switch to a safer chemical.
Most of the world's people live in poverty, he said, and their only way out is through industrial development. But if it's done the way Europe and the U.S. did it, "the ecological systems could not sustain such an onslaught."
"It is the responsibility of the global industrial community to help resolve this dilemma," Blanchard said, and to help find ways to raise up the world's poor "without bankrupting the environment."
However, Bromley said recent research on global atmospheric change has been laced with uncertainties and punctuated by "surprises."
Take chlorofluorocarbons (CFCs), for example. CFCs are best-known as the villainous refrigeration gases that are destroying the high-altitude ozone molecules that shield Earth from the sun's ultraviolet rays.
But, in addition, Bromley said, "we always thought that CFCs were among the most potent greenhouse gases," a class of natural and man-made chemicals that absorb the sun's energy and cause atmospheric warming.
Recent research has suggested that CFCs also destroy ozone at lower altitudes, where ozone, too, acts as a greenhouse gas.
Bromley said the study indicated that CFCs attack the ozone "such that if you add the effects . . . the greenhouse effect is zero."
L "It's a real surprise," he said, and there have been others.
These discoveries "give us clues to a much deeper understanding of Earth's ecological systems," Bromley said. But they also indicate that our understanding of global change "is much less certain than we thought."
"It is our firm conviction that unless we have a strong scientific understanding of the impact of our policies, there is no guarantee we are going in the right direction," he said.
Bromley said the Bush administration is spending $1.2 billion a year for atmospheric research. In the meantime, passage of the federal Clean Air Act of 1990 will reduce power plant emissions that contribute to global warming and set long-term carbon dioxide emission limits.
Spending requests for alternative fuel development will increase percent next year, Bromley said, and tree-planting programs will help turn atmospheric carbon back into trees.
But others at the meeting yesterday derided Bromley's viewpoint.
F. Sherwood Rowland, a co-discoverer of the CFC-ozone phenomenon, said Bromley "set a record for the most scientific errors in one talk," leading Rowland to question the quality of scientific advice President Bush is receiving.
For example, Bush's annual tree-planting program may have an impact on removing carbon dioxide from the atmosphere, but not for 4,000 years, Rowland said.
Others favor bolder action now.
"We don't always have the luxury of waiting," said Blanchard, the DuPont vice chairman. "Steps to mitigate such [atmospheric] effects must be taken as soon as possible."
Michael Oppenheimer, a chemist and senior scientists with the Environmental Defense Fund, agreed. "It would be imprudent to let uncertainties provide a barrier to action," he said.
Oppenheimer expressed optimism that with world leaders and the American public moving more rapidly than the United States government toward support for stronger policies to curb emissions of greenhouse and ozone-depleting gases, the administration's current lack of enthusiasm will eventually be seen as a "fluke of history."