Strong currents accelerate Antarctic ice meltJune 27th, 2011 - 12:25 pm ICT by IANS
Washington, June 27 (IANS) Strong ocean currents are eroding the ice beneath West
Antarctica’s Pine Island Glacier, accelerating its melting.
According to one estimate, the total collapse of Pine Island Glacier and its tributaries could raise sea level by 24 cm. Global sea levels are currently rising at about three mm a year.
The glacier is currently sliding into the sea at a clip of four km a year while its ice shelf is melting at about 80 cubic km a year, 50 percent faster than it was in the early 1990s, says a new study.
The glacier, among other ice streams in Antarctica, is being closely watched for its potential to redraw coastlines worldwide.
The researchers say that a growing cavity beneath the ice shelf has allowed more warm water to melt the ice - a process that feeds back into the ongoing rise in global sea levels, reports the journal Nature Geoscience.
“More warm water from the deep ocean is entering the cavity beneath the ice shelf, and it is warmest where the ice is thickest,” said Columbia University’s Lamont-Doherty Earth Observatory oceanographer Stan Jacobs, who led the study.
The researchers found that in 15 years, melting beneath the ice shelf had risen by about 50 percent. Although regional ocean temperatures had also warmed slightly, by 0.2 degrees Celsius or so, that was not enough to account for the jump, according to a Columbia statement.
The local geology offered one explanation. On the same cruise, a group led by Adrian Jenkins, a researcher at British Antarctic Survey and study co-author, sent a robot submarine beneath the ice shelf, revealing an underwater ridge.
One day, near the southern edge of Pine Island Glacier, researchers directly observed the strength of the melting process as they watched frigid, sea water appear to boil on the surface like a kettle on the stove.
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- Antarctic ice shelf faces threat from warm waters - May 10, 2012
- Warm ocean currents cause ice loss from Antarctica - Apr 26, 2012
- Melting glaciers on Arctic islands play major role in rise of sea level - Apr 21, 2011
- NZ glaciers melted as European expanded at the end of ice age - Sep 09, 2010
- Low-level aerial surveys aim to understand rapid Antarctic melting - Oct 08, 2009
- Global warming curbs won't prevent steep sea rise - Mar 21, 2012
- 'Reduction in Antarctic glacier ice could increase sea level' - Jun 23, 2010
- Melting ice in Canadian Arctic bigger player in sea-level rise - Apr 22, 2011
- Warming ocean layers melt polar ice sheets faster - Jul 04, 2011
- Believe it or not - glaciers are growing! - Jan 28, 2011
- Global wind-shift caused Earth's last ice age to end - Jun 26, 2010
- 'Water mining' prime culprit in rising sea levels - Oct 11, 2010
- How heat is transported to Greenland glaciers - Mar 29, 2011
- Some Antarctic ice is building up from bottom - Mar 04, 2011
Tags: adrian jenkins, british antarctic survey, coastlines, columbia university, deep ocean, doherty earth observatory, global sea levels, journal nature, lamont doherty earth observatory, local geology, ocean currents, ocean temperatures, oceanographer, pine island glacier, robot submarine, sea water, southern edge, strong currents, underwater ridge, west antarctica