Featured Research

from universities, journals, and other organizations

Speeding Antarctic Glacier: Scientists Discover Another Reason For Glacial Acceleration

Date:
November 19, 2008
Source:
University of Maine
Summary:
New satellite data have helped scientists crack the case of a speeding Antarctic glacier -- a finding that promises to help improve sea level forecasts.

Byrd Glacier, Antarctica
Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

New satellite data have helped scientists crack the case of a speeding Antarctic glacier -- a finding that promises to help improve sea level forecasts.

Using nearly 50 years of data, University of Maine researchers have determined that subglacial floods in East Antarctica caused a rapid and short-lived acceleration of a major outlet glacier.

Leigh Stearns and Gordon Hamilton of UMaine's Climate Change Institute, along with Benjamin Smith of the University of Washington, observed that the flow rate of a large outlet glacier in East Antarctica increased by about 10 percent in response to the flooding of two subglacial lakes.

The team's findings are based on a 48-year record of ice velocities along Byrd Glacier, East Antarctica along with recent satellite observations of ice surface elevation and ice velocities from NASA's Advanced Spaceborne Thermal Emission and Reflection Radiometer instrument on NASA's Terra satellite; the Ice, Cloud and Land Elevation Satellite; and Landsat; as well as SPOT and Japan's Advanced Land Observing Satellite, and have been reported in a Nature Geoscience paper.

"We saw that there was this very rapid acceleration of the glacier that we didn't initially have an explanation for," Hamilton said.

It wasn't until Stearns presented these observations at a conference last year that we recognized the connection between the glacier acceleration and the subglacial drainage event.

"After my presentation," explains Stearns, "Ben [Smith, co-author] and I compared the timing of the flooding event that he measured, and the acceleration of Byrd Glacier, and were excited to find that they occurred at roughly the same time."

The increase in ice flow speed coincides with rapid changes in ice surface elevation about 200 km upstream, which the research team interprets as the filling and draining of two subglacial lakes.

"Our work shows that the speed of the glacier can change by a very large amount," Hamilton said. "It only lasted for a year, but if the same process happens again at a larger scale, sea level could rise much quicker."

For the past year, some of the team's colleagues have been mapping subglacial lakes and discovered that they are quite prevalent.

"Our understanding of why they occur is minimal," Hamilton said, noting that it previously was thought that these lakes were stable and relatively inactive.

"The more we look, the more we see that these lakes fill up and drain," Hamilton said.

"One of the implications of this work," explains Stearns, "is that the addition of even a small amount of water to the bottom of a glacier can cause significant acceleration. While the changes taking place on Byrd Glacier are not caused by climate-driven processes, they highlight the sensitivity of glaciers to small changes."

Future investigations are expected to look at other subglacial lakes to measure their activity and determine how to include subglacial flooding in current ice sheet models for more accurate predictions of sea level changes.

"We need to include all the important processes that cause the ice sheets to grow and shrink," Hamilton said.


Story Source:

The above story is based on materials provided by University of Maine. Note: Materials may be edited for content and length.


Cite This Page:

University of Maine. "Speeding Antarctic Glacier: Scientists Discover Another Reason For Glacial Acceleration." ScienceDaily. ScienceDaily, 19 November 2008. <www.sciencedaily.com/releases/2008/11/081118144857.htm>.
University of Maine. (2008, November 19). Speeding Antarctic Glacier: Scientists Discover Another Reason For Glacial Acceleration. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2008/11/081118144857.htm
University of Maine. "Speeding Antarctic Glacier: Scientists Discover Another Reason For Glacial Acceleration." ScienceDaily. www.sciencedaily.com/releases/2008/11/081118144857.htm (accessed April 20, 2014).

Share This



More Earth & Climate News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drought Concerns May Hurt Lake Tourism

Drought Concerns May Hurt Lake Tourism

AP (Apr. 18, 2014) Operators of recreational businesses on western reservoirs worry that ongoing drought concerns will keep boaters and other visitors from flocking to the popular summer attractions. (April 18) Video provided by AP
Powered by NewsLook.com
Man Claims He Found Loch Ness Monster With... Apple Maps?

Man Claims He Found Loch Ness Monster With... Apple Maps?

Newsy (Apr. 18, 2014) Andy Dixon showed the Daily Mail a screenshot of what he believes to be the mythical beast swimming just below the lake's surface. Video provided by Newsy
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
Ark. Man Finds 6-Carat Diamond At State Park

Ark. Man Finds 6-Carat Diamond At State Park

Newsy (Apr. 18, 2014) An Arkansas man has found a nearly 6.2-carat diamond, which he dubbed "The Limitless Diamond," at the Crater of Diamonds State Park. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins