THE SCOOP on global warming

Warmer temperatures, rising sea levels, and shifting rainfall patterns?

"Climate changes," observes Daniel Sarewitz. "Let's deal with it."

His approach appears at odds with global efforts to reduce humanity's impact on climate by cutting the amount of heat-trapping gases pumped into the atmosphere each year.

But to Dr. Sarewitz and a growing number of analysts, adapting to climate change is an approach that has been overlooked for too long. In the end, they say, adaptation may prove more effective than trying to control emissions in easing the impact of climate change on human activities.

This does not sit well with hard-core conservationists, who, since climate change burst to the fore as a global environmental issue in the 1980s, view adaptation as a form of environmental appeasement.

Next Monday, diplomats from 160 countries meet in the Netherlands to begin an 11-day negotiating marathon designed to write the rules under which countries that ratify the 1997 Kyoto Protocols would operate. Under the protocols, nations would be required to cut their collective CO2 emissions by at least 5 percent between 2008 and 2012.

Yet even if every nation on the planet were to ratify and implement the pact, "Kyoto is not going to reverse climate trends," says Sarewitz, a senior research scholar at Columbia University's Center for Science, Policy, and Outcomes. "Its impact on carbon dioxide is relatively trivial."

"The simple truth is we don't have a way of figuring out how to keep CO2 from doubling" during the 21st century, adds Jerry Mahlman, recently retired director of the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory at Princeton University.

Based on doubling atmospheric CO2, the United Nation's International Panel on Climate Change (IPCC) now estimates that global temperatures will rise an average of 1.5 to 6 degrees Celsius (2.7 to 10.8 degrees F.) between 1990 and 2100.

Trends in CO2 emissions and their projected effects on climate, Sarewitz says, make a strong case for giving adaptation - from improved hazard mapping, weather forecasts and warnings, and building codes to more environmentally responsible land-use practices - a higher spot on the international climate-change agenda.

The concept of adaptation is hardly new, notes Roger Pielke, who studies the interplay between science and climate policy at the National Center for Atmospheric Research (NCAR) in Boulder, Colo.

"Adaptation to climate is something we do all the time," he says. Nor would all the effects from climate change be harmful. But, he adds, the issue is taking on greater importance because "losses are certain to rise" worldwide as changing climate alters regional weather patterns and as population and wealth grow.

Indeed, he and others argue that if governments are concerned about an increase in severe weather, they don't need 100-year climate forecasts to prepare, since severe weather, floods, and other extreme events happen regularly enough today. Thus, for example, restricting the development of barrier islands not only reduces society's immediate vulnerability to hurricanes; it also reduces vulnerability to hurricanes decades hence.

Yet even without global warming as an incentive, efforts to adapt based on past experience or even on impending climate swings have a checkered record.

In 1998, Hurricane Mitch made landfall over Honduras and Nicaragua. It wasn't the first time portions of Central America had been devastated by tropical cyclones. Yet of the $5 billion in aid that Honduras received, 80 percent went to the towns devastated by floods and mudslides.

The towns "rebuilt in harm's way," says Michael Glanz, an NCAR scientist who last month completed a study of global responses to the 1997-98 El Nino for the UN.

There, too, he says, results were mixed. Knowing in advance that El Nino was building, Peru borrowed money from international lenders to pay for projects such as clearing storm drains and river channels to reduce flooding. Yet leaders there still tend to view El Nino as a temporary event, rather than a recurring condition that needs to be taken into account for establishing building codes or zoning land, Dr. Glanz says.

"The good news is that our findings are not inconsistent with other studies" on how countries respond to El Nino, he says. "The key question is: Why are the solutions known but not applied?"

In trying to anticipate the effects of global warming, several governments have tried to estimate how rising average temperatures would play out in their regions.

Earlier this year, for example, the US Global Change Research Program took its first cut at gauging the impact of climate change on different parts of the country. It estimated that if average temperatures rise by 5 to 10 degrees F., the frequency of winter rains hitting Southern California and the Southwest could increase dramatically, while snowpack in ranges such as the Rockies could fall by 50 percent.

If sea levels rise another 35 inches during the 21st century, the US could lose 4,000 square miles of coastal wetlands.

Within the past week, a team of scientists in Britain published a similar set of projections for Britain and Europe. The report estimates that southern Europe will dry out, while northern Europe could see substantial increases in rain. Such changes, the team says, could have serious effects on farming and electricity production from dams in the south.

Estimates from the IPCC look substantially more perilous for Pacific Island countries and low-lying nations like Bangladesh if sea-levels rise significantly.

Under such conditions, "it's morally unacceptable not to think about vulnerability and adaptation," Sarewitz says.

Indeed, the USCGP suggests that the direct economic effects to the US from climate change may be "modest" because "American society could likely be able to adapt" to the majority of changes the country undergoes.

How society responds to changing weather patterns plays a bigger role in determining the size of climate-change related losses than the climate itself, Pielke says.

He, Sarewitz, and Roberta Klein, also with NCAR, were curious to see how sensitive the International Panel on Climate Change's estimates of damage from hurricanes, typhoons, and tropical cyclones were to shifts in climate and in societal factors.

Using the IPCC's assumptions, they calculated that if population and wealth are held constant and the climate warms, dollar losses from severe tropical weather worldwide would grow by roughly 10 percent between 2000 and 2050.

If climate is held constant but social factors change as the IPCC envisions, damage-cost estimates during the same period would rise nearly 500 percent.

Pielke and his colleagues, who published their study in the journal Energy & Environment earlier this year, suggest that the pattern would hold for other climate-change related hazards, such as droughts and flooding.

If the concept of adaptation has met resistance in the past, the resistance may be faltering.

"Adaptation is necessary," says Michael Oppenheimer, chief scientist at Environmental Defense, a New York-based environmental group. But it needs to work in concert with emissions reductions, he continues. "You need sensible policies on both ends" of the problem.

Pielke and Sarewitz say a key starting point is to pump more money into research on natural hazards and the most effective ways to blunt their effects.

The researchers note that the Framework Convention on Climate Change, under whose auspices leaders will meet in The Hague next week, spent more on itself in one year than donor countries spent on efforts to address natural disasters during all of the UN's International Decade of Natural Disaster Reduction, which ran throughout the 1990s.

The US Agency for International Development has embarked on a five-year, $200 million-a-year effort to help countries measure and monitor greenhouse-gas emissions. But the agency spent only $17 million in 1997 for disaster preparedness and prevention projects.

These spending patterns, the researchers say, fail to fund actions that can have a more immediate effect on reducing human vulnerability to climate change than trying to turn "the big knob" of global energy use.

Additional money could be earmarked for projects ranging from mapping the extent of flood or other severe-weather hazards a community or country may face to supporting efforts to adopt and enforce more stringent building and land-use codes.

Stemming the loss of forests and wetlands in key locations would help reduce the effects of floods - as well as provide a sink for carbon dioxide.

These approaches also are closely linked to issues of poverty and public health, which would need to be addressed, the researchers say.

Politically, such approaches to climate change may be an easier sell than leaning on broader policy changes that affect energy use and economic growth.

With adaptation measures, the immediacy of tomorrow's weather means "there's a reason for doing this now" that isn't as burdened with the uncertainties surrounding long-range climate forecasts, Sarewitz says.

More broadly, such approaches split one large hard-to-turn knob into a series of smaller, easier-to-turn knobs, the researchers say, giving humanity more options as it faces a world in which climate changes - with or without human hands.

"We have the expertise" to deal with these issues, Pielke says. "We're just maladapted."

(c) Copyright 2000. The Christian Science Publishing Society