Wednesday, February 25, 2009

Antarctic Red Flag: Glaciers Sliding More Rapidly Than Expected

A study by a team of scientists in Antarctica suggests that a number of large glaciers on the icy continent are speeding up, risking higher sea levels sooner than expected.

According to the scientists, the ice in West Antarctica, which had been thought to be fairly stable, is showing signs of significant melting and shifting. For example, the massive Pine Island Glacier in West Antartica is moving 40 percent faster than a few decades ago, while the smaller Smith Glacier is already 83 percent faster than it was just 15 years ago.

Some of the researchers expressed surprise, as they had expected to find evidence of warming on the Antarctic Peninsula, a relatively small area, but not in the huge area represented by West Antarctica.

This is bad news indeed, as it suggests--along with other evidence of late--that time is running out faster than scientists had expected just a few years ago. While there's been a lot of talk about the extent of sea ice melting in the Arctic recently, melting sea ice doesn't raise sea levels. The Antarctic glaciers, however, are on land, so to the extent they slide into the ocean at a faster rate, they will raise sea levels.

Significantly, the most recent IPCC report on climate change (in 2007) really ignored the potential for sea rises from melting in Antarctica and Greenland because there simply wasn't enough evidence to make a valid estimate. The IPCC report forecast sea level rises of between 7-23 inches by the year 2100, but the additional melting in Antarctica could easily double that.

At the far extreme, the data from West Antarctica raises the specter of a complete collapse of the West Antarctic ice sheet at some point in the future, which would raise sea levels by several feet, and which, if it occurred, could happen over a short period of time.

The good news about the global recession is that greenhouse gas emissions in 2009 will undoubtedly decrease simply due to less industrial activity. The bad news is that nations will be reluctant to make investments in somewhat more expensive alternative energy, paving the way for a rapid increase in emissions when economic expansion resumes.

One wonders whether it is already too late to stop the most significant effects of climate change. Because most of the effects will be felt gradually over the next 100 years, we doubt that it will be quite as catastrophic as some doomsayers predict; by the same token, we are confident that the impact will be quite large, and the effects unpredictable.

One U.S. state that ought to be plenty worried is Governor Bobby Jindal's Louisiana. The low-lying, marshy, swampy state could find itself in big trouble with even a modest sea level rise. There was no sign in Jindal's GOP response to Obama's speech last night that he is the least bit concerned.

The new data from Antarctica is just one more red flag.

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