COPENHAGEN

All eyes are on Greenland's melting glaciers as alarm about global warming spreads. This year, delegations of U.S. and European politicians have made pilgrimages to the fastest-moving glacier at Ilulissat, where they declare that they see climate change unfolding before their eyes.

Curiously, something that's rarely mentioned is that temperatures in Greenland were higher in 1941 than they are today. Or that melt rates around Ilulissat were faster in the early part of the past century, according to a new study. And while the delegations first fly into Kangerlussuaq, about 100 miles to the south, they all change planes to go straight to Ilulissat -- perhaps because the Kangerlussuaq glacier is inconveniently growing.

I point this out not to challenge the reality of global warming or the fact that it's caused in large part by humans, but because the discussion about climate change has turned into a nasty dustup, with one side arguing that we're headed for catastrophe and the other maintaining that it's all a hoax. I say that neither is right. It's wrong to deny the obvious: The Earth is warming, and we're causing it. But that's not the whole story, and predictions of impending disaster just don't stack up.

We have to rediscover the middle ground, where we can have a sensible conversation. We shouldn't ignore climate change or the policies that could attack it. But we should be honest about the shortcomings and costs of those policies, as well as the benefits.

Environmental groups say that the only way to deal with the effects of global warming is to make drastic cuts in carbon emissions -- a project that will cost the world trillions (the Kyoto Protocol alone would cost $180 billion annually). The research I've done over the last decade, beginning with my first book, "The Skeptical Environmentalist," has convinced me that this approach is unsound; it means spending an awful lot to achieve very little. Instead, we should be thinking creatively and pragmatically about how we could combat the much larger challenges facing our planet.

Nobody knows for certain how climate change will play out. But we should deal with the most widely accepted estimates. According to the United Nations' Intergovernmental Panel on Climate Change (IPCC), ocean levels will rise between half a foot and two feet, with the best expectation being about one foot, in this century, mainly because of water expanding as it warms. That's similar to what the world experienced in the past 150 years.

Some individuals and environmental organizations scoff that the IPCC has severely underestimated the melting of glaciers, especially in Greenland. In fact, the IPCC has factored in the likely melt-off from Greenland (contributing a bit over an inch to sea levels in this century) and Antarctica (which, because global warming also generally produces more precipitation, will actually accumulate ice rather than shedding it, making sea levels two inches lower by 2100). At the moment, people are alarmed by a dramatic increase in Greenland's melting. This high level seems transitory, but if sustained it would add three inches, instead of one, to the sea level rise by the end of the century.

A one-foot rise in sea level isn't a catastrophe, though it will pose a problem, particularly for small island nations. But let's remember that very little land was lost when sea levels rose last century. It costs relatively little to protect the land from rising tides: We can drain wetlands, build levees and divert waterways. As nations become richer and land becomes a scarcer commodity, this process makes ever more sense: Like our parents and grandparents, our generation will ensure that the water doesn't claim valuable land.

The IPCC tells us two things: If we focus on economic development and ignore global warming, we're likely to see a 13-inch rise in sea levels by 2100. If we focus instead on environmental concerns and, for instance, adopt the hefty cuts in carbon emissions many environmental groups promote, this could reduce the rise by about five inches. But cutting emissions comes at a cost: Everybody would be poorer in 2100. With less money around to protect land from the sea, cutting carbon emissions would mean that more dry land would be lost, especially in vulnerable regions such as Micronesia, Tuvalu, Vietnam, Bangladesh and the Maldives.

As sea levels rise, so will temperatures. It seems logical to expect more heat waves and therefore more deaths. But though this fact gets much less billing, rising temperatures will also reduce the number of cold spells. This is important because research shows that the cold is a much bigger killer than the heat. According to the first complete peer-reviewed survey of climate change's health effects, global warming will actually save lives. It's estimated that by 2050, global warming will cause almost 400,000 more heat-related deaths each year. But at the same time, 1.8 million fewer people will die from cold.