Yet researchers are already aware that some degree of change seems to be under way. For example, the Arctic is warming. Air circulation around the North Pole region has changed. It is bringing warmer, wetter winters to northern Europe, Siberia, and parts of North America. Also, a changed wind pattern is moving young Arctic ice out of the ocean faster. That means it doesn't linger as long and build up its former thickness.
Dorothy Peteet from the NASA Goddard Institute for Space Science in New York—and NRC committee member—notes the Arctic is a good region to explore climate questions. There could well be a climate switch, which might be as simple as permafrost melting. Among other things, that could release methane, a powerful greenhouse gas.
The NRC committee members realize they are sounding a warning that is cloaked in uncertainty. Therefore, they urge what they call a "no regrets" policy: Take no action based on vague fear. Do take actions that will be beneficial, whatever happens. These include measures to curb global warming.
Continue to work to ensure adequate resources of clean air and water. Build resiliency into economic systems. And support the extensive research needed to understand how the climate system works.
Alley says scientists need to face up to a certain amount of inevitable uncertainty, since natural processes may throw climate switches in random ways that are impossible to forecast. To help people learn to anticipate surprises, he says, "We need to build uncertainty into our models of climate change."
Copyright 2001 The Christian Science Monitor
