Peter Clark, David Braaten, Hugh Ducklow, Douglas Martinson, Chris Field: Antarctica is heating up fast scientists warn

Antarctica is heating up fast, a Kansas researcher and other scientists warn

by Scott Canon, Tricity Herald, March 8, 2009

KANSAS CITY, Mo. -- No longer is David Braaten constantly cocooned in his red super parka. He left the insta-freeze winds of the Antarctic interior in January.

But as cold as the trip was for the University of Kansas scientist, he recognizes what one discovery after the next has demonstrated this year: It's getting remarkably warm for down there, and it's heating up incredibly fast.

"We're trying to find out what's happening to the ice," said Braaten, the deputy director of the KU-based Center for Remote Sensing of Ice Sheets.

Even as changing climate brings more moisture, and ice, to Antarctica's center, on its edges the frozen continent is becoming less so. Melting skyscrapers of ice crash into the ocean at ever faster rates.

That's raising sea levels, disrupting ocean food chains and reducing the region's ability to moderate the planet's climate.

Climate scientists once were befuddled about why Antarctica seemed, if anything, to be cooling while the rest of the world got toastier. It turns out the bottom of the world has been warming after all.

"More is happening than we thought, and it's happening faster," said Douglas Martinson, who studies the impact of polar oceans on global climate at Columbia University.

Average winter temperatures on the Antarctica peninsula -- changing more than the rest of the continent -- have risen 11 degrees since 1950. That's five times the global warm-up and disastrous to the ice shelves that hang over water and act as corks to bottle up glaciers on land.

In 1950, the Wilkins Ice Shelf was bonded to Antarctica with a 62-mile wide block of ice. Now it clings by an hourglass-shaped link that narrows to just a third of a mile. The Jamaica-size shelf could tumble into the ocean any time.

Last week, the World Meteorological Organization said northern Arctic sea ice shrunk to its lowest in the summers of 2007 and 2008 since satellites began watching 30 years ago.

The Southern Ocean, meanwhile, is warming at rates faster than the rest of the Earth.

"We are basically looking now at a future climate that's beyond anything we've considered seriously," Chris Field of Stanford University told a meeting in Chicago.

In 2007, the Intergovernmental Panel on Climate Change won a Nobel Prize for its scientific consensus on the reality of global warming from human activity. Fresh research suggests the vaunted report lowballed the pace of the problem.

The changes seen now are much faster and parallel the increase in greenhouse gases such as carbon dioxide.

The National Oceanic and Atmospheric Administration said in January that although 2008 was one of the world's coolest years this decade, it was still the ninth warmest on record. Since 1880, 10 of the warmest years are since 1997.

A recent column by conservative George Will, in which he argued that concerns about global warming were overwrought and unfounded, was condemned by mainstream climate scientists both for his conclusion and his specifics.

For instance, he said that "global sea ice levels now equal those of 1979." But the very authority he cited, the University of Illinois' Arctic Climate Research Center, said the amount of sea ice in the world was down about 8% over the last three decades, or the equivalent of "Texas, California and Oklahoma combined."

The West Antarctic Ice Sheet covers a third of the continent as well as great expanses of the Weddell and Ross seas.

Fortunately, no one foresees its collapse for centuries, as it could be more catastrophic than previously understood. A recent paper in the journal Science predicted it would shift the planet's axis by a third of a mile and send rising waters sloshing northward.

"It's the difference between spinning a ball with a lump of something on the side, or taking that material and distributing it more evenly around the surface," said Peter Clark, a geosciences professor at Oregon State University.

Scientists had believed such an ice dump would universally raise ocean levels 16.5 feet worldwide, but new computer modeling suggests the shores of North America could face yet five feet more of water.

Braaten and his colleagues try to sort out the complicated question of how much ice still exists. They experiment with high-tech flights to decipher how deep the snow and ice is.

"When you're there, you just see that it looks flat," Braaten said. "Flatter than Nebraska."

But beneath -- the glaciers average 1.5 miles thick in Eastern Antarctica -- sit undulating mountain ranges for Braaten and his colleagues to chart.

Understanding that terrain below and the glaciers piled on top will offer a better idea how much ice may be accumulating in Antarctica's middle -- a consequence of climate change bringing more moisture to the region -- and how much is calving away at the edges.

Particularly on the Antarctica peninsula to the west, the rapid retreat of sea ice has profound consequences for penguins and other wildlife.

"Penguins and seals and whales need that sea ice," said Hugh Ducklow, who also returned from Antarctica to the Marine Biological Laboratory in Woods Hole, Mass. "All these ice-loving species are contracting their ranges to the south," chasing after the ice.

The average time per year the ocean around the peninsula is covered by sea ice has fallen by 90 days since 1978. Whaling records suggest the ice began to withdraw as early as the 1930s.

That's meant tiny invertebrates like krill -- which hide from predators and feed on plant matter that grows in the ice -- decline when the ice declines. So do the fish that feed on them, and so on.

"The Arctic was the canary in the coal mine, and we didn't pay much attention when it got sick," said Martinson. "Now the penguins are the canaries down there, and they're not looking too good."

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