Monday, May 22, 2006

Scare of the Century

The cover story of the latest issue of the National Review calls global warming the scare of the century.

Jason Lee Steorts takes Time magazine to task for declaiming that:

“In the past five years or so, the serious debate has quietly ended. Global warming, even most skeptics have concluded, is the real deal, and human activity has been causing it.”

By whom is more like it but Time doesn't mention this. The National Revie article is subscriber-only so here are some key points:

- It's land ice, stupid.

The world has two major ice sheets, one covering most of Greenland and the other covering most of Antarctica. While melting sea ice has captured its share of attention, it’s the land sheets that matter. Sea ice is already in the water, so its melting doesn’t raise ocean levels. But if land ice melts, the sea gets higher. Time wants you to be very worried about this: “By some estimates, the entire Greenland ice sheet would be enough to raise global sea levels 23 ft., swallowing up large parts of coastal Florida and most of Bangladesh. The Antarctic holds enough ice to raise sea levels more than 215 ft.”
About Antarctica, University of Virginia climate scientist Patrick J. Michaels is direct: “What has happened is that Antarctica has been gaining ice.” He explains that there has been a cooling trend over most of Antarctica for decades. At the same time, one tiny portion of the continent — the Antarctic Peninsula — has been warming, and its ice has been melting. The peninsula constitutes only about 2 percent of Antarctica’s total area, but almost every study of melting Antarctic ice you’ve heard of focuses on it.
In 2002, Nature published a study by Peter Doran that looked at Antarctic temperature trends from 1966 to 2000. What it found was that about two-thirds of Antarctica got colder over that period. At the same time, Antarctica has gotten snowier, and as the snow has accumulated the ice sheet has grown. Snowfall is probably rising because water temperatures around Antarctica have gotten slightly — repeat, slightly — warmer. As a result, there is more surface evaporation, making for higher humidity and more precipitation. Higher humidity also means more clouds, which might explain the cooler weather.
And Greenland? Various studies show that warmer temperatures are causing the ice sheet there to lose mass at the margins. But, as in Antarctica, higher sea temperatures are also causing greater snowfall and building up ice in the interior. As Richard Lindzen of MIT observes, “If you’re just going to look at what’s falling off the sides and ignore what’s collecting on top, that’s not exactly kosher.”

- Part of a cycle?

What we know is that the global average temperature has risen by about 1 degree Celsius or less since the late 1800s. We also know that industrial activity has raised atmospheric carbon-dioxide concentrations, and that this increase should make things warmer. But there is wide disagreement about the extent to which carbon-dioxide emissions are responsible for the warming we’ve seen so far, and how much warming they will cause in the future.

Fred Singer of George Mason University points out that “we have historic [temperature] records in Europe going back a thousand years. It was much warmer then than today. The Arctic was much warmer a thousand years ago than it is today. Polar bears survived. The ice caps survived.” And data from ice cores suggest that previous interglacial periods were warmer than the one we’re going through now.

- Research bias?

Richard Lindzen of MIT thinks that, while most scientists were originally agnostic on the question whether human activity was causing global warming, “environmentalists and the media would exaggerate.” That eventually built up a public concern, and politicians responded by throwing research dollars at scientists. If global warming turned out not to be a problem, those dollars would go away. Better to keep us worried: “You’ve developed a scientific community that will do whatever it needs to do to make sure the answer isn’t obtained. Why should taxpayers pay for people not to find an answer?”

- Kyoto is a p*ss in the wind

Of course, even if man-made global warming is the primary cause of the mild temperature and sea-level rises being observed, this doesn’t settle the question of what to do about it. The environmental lobby’s answer is: Ratify the Kyoto Protocol. Time isn’t even subtle about it, calling George W. Bush’s environmental record “dismal” and specifically citing his abandonment of Kyoto. But he abandoned it for good reason. The U.S. Energy Information Administration estimates that the treaty would cost the American economy $300 billion to $400 billion a year. Any decision about whether to pay such a price should be based on cost-benefit analysis. What, then, is the benefit?

In a word, nothing. Kyoto wouldn’t stop whatever warming is caused by greenhouse-gas emissions; it would just slow it. And it would barely do that. Tom Wigley of the National Center for Atmospheric Research calculated that the full global implementation of Kyoto would prevent 0.07 degrees Celsius of global warming by 2050, an outcome that is all but undetectable. To put a dent in CO2 levels, you’d need much greater emissions reductions than Kyoto calls for. Jerry Mahlman of the National Center for Atmospheric Research, for example, has called Kyoto a “first step” and said that “30 Kyotos might do the job.”

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