More than 300 glaciers on the Antarctic Peninsula are flowing faster into the ocean, further adding to sea level rise, according to research published this week in the Journal of Geophysical Research.
The researchers, members of the British Antarctic Survey, said warming temperatures, which have already increased summer snow melt and ice shelf retreat on the peninsula, were the most likely cause.
"The Antarctic Peninsula has experienced some of the fastest warming on Earth, nearly three degrees Celsius (5.4 degrees Fahrenheit) over the last half-century," lead study author Hamish Pritchard said in a statement. "Eighty-seven percent of its glaciers have been retreating during this period and now we see these glaciers are also speeding up" as they discarge ice and water into the ocean.
Using radar images from satellites, the researchers tracked the flow rate of more than 300 previously unstudied glaciers on the peninsula's west coast and found a 12 percent increase in glacier speed from 1993 to 2003.
During those 10 years, the annual increase in sea levels from the area was estimated at 0.02 inches.
Factoring in that rate, the overall annual sea level increase from glaciers across the Antarctic Peninsula was estimated at .16 inches a year.
"This is comparable to the contribution from Alaskan glaciers, and combined with estimated mass loss from West Antarctica, is probably large enough to outweigh mass gains in East Antarctica and to make the total Antarctic sea level contribution positive," the researchers stated.
The BAS said the results echo recent findings from coastal Greenland. In both cases, the cause thought to be the melting of lower glaciers, which flow directly into the sea.
"As they thin, the buoyancy of the ice can lift the glaciers off their rock beds, allowing them to slide faster," the BAS stated.
The BAS noted that the U.N. Intergovernmental Panel on Climate Change earlier this year reported that it could not estimate an upper limit on sea-level rise from Antarctica because not enough was known about how ice sheets behaved.
"These new results give scientists a clearer picture about the way that climate warming can affect glaciers both in the Arctic and Antarctic," the BAS said. "Furthermore, they pave the way for more reliable projections of future sea level rise, and provide a better basis for policy decisions."
Pritchard emphasized the importance of satellites in such studies.
"It’s important that we use tools such as satellite technology that allow us to monitor changes in remote and inaccessible glaciers on a regional scale," he said. "Understanding what’s happening now gives us our best chance of predicting what’s likely to happen in the future."
It was revealed on Monday that the Bush administration has cut back on climate studies via satellites.