Tuesday, November 17, 2009

Ice retreat creates new CO2 store

Glacier, Antarctic (Image: BAS)It is like finding a forest the size of Wales that nobody knew was there before...

Retreating ice in Antarctic has allowed tiny aquatic plants to flourish and absorb 3.5 million tonnes of carbon from the ocean and atmosphere annually.

Researchers from the British Antarctic Survey say the new "carbon sink" of phytoplankton is equivalent to discovering a forest the size of Wales.

However, the authors added, the discovery would only have a "minuscule effect on climate change".

The findings have been published in the journal Global Change Biology.

"What we are talking about are are large ice shelves the size of an English county," explained lead author Lloyd Peck, a marine biologist for the British Antarctic Survey.

"When they disappear, we are getting new pieces of sea," he explained.

"In the past, you could not have had life where the ice was because it was perhaps 500m thick and stopped all light coming in. Once it had gone, then you have new areas for light to colonise."

Writing in the paper, Professor Peck and his colleagues observed: "A range of feedback mechanisms affecting climate change have been identified.

"These feedbacks are almost universally positive, enhancing rates of climate warming."

These included the warming of sea and air that led to a loss of ice cover, which in turn had reduced the amount of solar energy being reflected back into space by ice (the albedo effect).

Current major carbon sinks - forests and oceanic phytoplankton blooms - were also under threat, they added.

"The loss of glaciers and ice shelves is also thought of as a factor that will predominantly increase warming of the Earth because of changes in albedo and heat take-up in newly uncovered ground and ocean.

But, they said, the loss of ice cover resulted in the "opening up of new areas for biological productivity".

via BBC NEWS | Science & Environment | Ice retreat creates new CO2 store.

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