Featured Research

from universities, journals, and other organizations

Scientists predict faster retreat for Antarctica's Thwaites Glacier; Underwater ridge critical to future flow

Date:
November 1, 2011
Source:
The Earth Institute at Columbia University
Summary:
The retreat of Antarctica's fast-flowing Thwaites Glacier is expected to speed up within 20 years, once the glacier detaches from an underwater ridge that is currently holding it back, according to a new study. The study is the latest to confirm the importance of seafloor topography in predicting how these glaciers will behave in the near future.

New seafloor topography off Antarctica’s Thwaites Glaciers leads scientists to predict accelerated melting in the next 20 years.
Credit: Frank Nitsche, Lamont-Doherty

The retreat of Antarctica's fast-flowing Thwaites Glacier is expected to speed up within 20 years, once the glacier detaches from an underwater ridge that is currently holding it back, says a new study in Geophysical Research Letters.

Related Articles


Thwaites Glacier, which drains into west Antarctica's Amundsen Sea, is being closely watched for its potential to raise global sea levels as the planet warms. Neighboring glaciers in the Amundsen region are also thinning rapidly, including Pine Island Glacier and the much larger Getz Ice Shelf. The study is the latest to confirm the importance of seafloor topography in predicting how these glaciers will behave in the near future.

Scientists had previously identified a rock feature off west Antarctica that appeared to be slowing the glacier's slide into the sea. But this study is the first to connect it to a larger ridge, using geophysical data collected during flights over Thwaites Glacier in 2009 under NASA's Ice Bridge campaign. The newly discovered ridge is 700 meters tall, with two peaks -- one that currently anchors the glacier and another farther off shore that held the glacier in place between 55 and 150 years ago, according to the authors.

The goal of NASA's Ice Bridge campaign is to map the topography of vulnerable regions like this in Antarctica and Greenland by flying over the ice sheets with ice-penetrating radar and other instruments.

The discovery that Thwaites is losing its grip on a previously unknown ridge has helped scientists understand why the glacier seems to be moving faster than it used to.

As scientists map the contours of the seafloor in the Amundsen Sea region, they are forming a clearer picture of what the glaciers are doing.In 2009, researchers sent a robot submarine beneath Pine Island Glacier's floating ice tongue and discovered a ridge about half the size of the one off Thwaites Glacier. Researchers estimate that Pine Island Glacier lifted off that ridge in the 1970s, allowing warm ocean currents to melt the glacier from below. The glacier's ice shelf is now moving 50 percent faster than it was in the early 1990s, Lamont-Doherty oceanographer Stan Jacobs and colleagues detailed in a study in Nature Geoscience earlier this year. Pine Island Glacier is moving into the sea at the rate of 4 kilometers a year -- four times faster than the fastest-moving section of Thwaites.

Lamont-Doherty geophysicist Robin Bell, study co-author, compares the ridge in front of Thwaites to a person standing in a doorway, holding back a crowd. "Knowing the ridge is there lets us understand why the wide ice tongue that used to be in front of the glacier has broken up," she said. "We can now predict when the last bit of floating ice will lift off the ridge. We expect more ice will come streaming out of the Thwaites Glacier when this happens."

"The bathymetry is the roadmap for how warm ocean water reaches the edges of the ice sheet," she added. "Ridges like this one and the one discovered in front of Pine Island Glacier stabilize ice sheets, but can also be a critical part of the destabilizing process."


Story Source:

The above story is based on materials provided by The Earth Institute at Columbia University. Note: Materials may be edited for content and length.


Journal Reference:

  1. K. J. Tinto, R. E. Bell. Progressive unpinning of Thwaites Glacier from newly identified offshore ridge: Constraints from aerogravity. Geophysical Research Letters, 2011; 38 (20) DOI: 10.1029/2011GL049026

Cite This Page:

The Earth Institute at Columbia University. "Scientists predict faster retreat for Antarctica's Thwaites Glacier; Underwater ridge critical to future flow." ScienceDaily. ScienceDaily, 1 November 2011. <www.sciencedaily.com/releases/2011/10/111026162707.htm>.
The Earth Institute at Columbia University. (2011, November 1). Scientists predict faster retreat for Antarctica's Thwaites Glacier; Underwater ridge critical to future flow. ScienceDaily. Retrieved April 22, 2015 from www.sciencedaily.com/releases/2011/10/111026162707.htm
The Earth Institute at Columbia University. "Scientists predict faster retreat for Antarctica's Thwaites Glacier; Underwater ridge critical to future flow." ScienceDaily. www.sciencedaily.com/releases/2011/10/111026162707.htm (accessed April 22, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Wednesday, April 22, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Maine Storm Surge Sparks Power Explosions

Raw: Maine Storm Surge Sparks Power Explosions

AP (Apr. 21, 2015) — Police dash cam video shows a series of explosions along the beach in Maine as heavy storm surge soaked electrical transformers. (April 21) Video provided by AP
Powered by NewsLook.com
Searching For The Loch Ness Monster? Try Google Street View

Searching For The Loch Ness Monster? Try Google Street View

Newsy (Apr. 21, 2015) — For the anniversary of the notorious "Surgeon&apos;s Photo" of the Loch Ness monster, Google used Street View to let those online join the search. Video provided by Newsy
Powered by NewsLook.com
Going Ape: Sierra Leone Chimpanzees Hail Ebola Retreat

Going Ape: Sierra Leone Chimpanzees Hail Ebola Retreat

AFP (Apr. 21, 2015) — As money runs out at Tacugama Chimpanzee Sanctuary in Sierra Leone, around 85 chimps are facing homelessness. The centre closed when the Ebola epidemic was ravaging the country but now that closure is beginning to look permanent. Video provided by AFP
Powered by NewsLook.com
Solar Plane Completes 6th Leg of Quest to Circumnavigate Globe

Solar Plane Completes 6th Leg of Quest to Circumnavigate Globe

AFP (Apr. 21, 2015) — Solar Impulse 2 lands in the Chinese city of Nanjing, finishing the sixth stage of its landmark 12-leg quest to circumnavigate the globe powered only by the sun. Duration: 00:42 Video provided by AFP
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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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