Featured Research

from universities, journals, and other organizations

Underlying ocean melts ice shelf, speeds up glacier movement

Date:
September 12, 2013
Source:
Penn State
Summary:
Warm ocean water, not warm air, is melting the Pine Island Glacier's floating ice shelf in Antarctica and may be the culprit for increased melting of other ice shelves, according to an international team of researchers.

The Pine Island Glacier expedition deployed multiple, unique sensor packages, developed by NPS Research Professor Tim Stanton, through 500 meters of solid ice to determine exactly how quickly warm water was melting the massive glacier from beneath. Pictured is the drill camp at the Pine Island Ice Shelf. The galley is on the left, hot water drill equipment in the center left, surface infrastructure tower mid right, and the seismic sled on the right.
Credit: Image courtesy of Tim Stanton/NPS

Warm ocean water, not warm air, is melting the Pine Island Glacier's floating ice shelf in Antarctica and may be the culprit for increased melting of other ice shelves, according to an international team of researchers.

Related Articles


"We've been dumping heat into the atmosphere for years and the oceans have been doing their job, taking it out of the air and into the ocean," said Sridhar Anandakrishnan, professor of geosciences, Penn State. "Eventually, with all that atmospheric heat, the oceans will heat up."

The researchers looked at the remote Pine Island Glacier, a major outlet of the West Antarctic Ice Sheet because it has rapidly thinned and accelerated in the recent past.

"It has taken years and years to do the logistics because it is so remote from established permanent bases," said Anandakrishnan.

Pine Island Glacier or PIG lies far from McMurdo base, the usual location of American research in Antarctica. Work done in the southern hemisphere's summer, December through January 2012-13, included drilling holes in the ice to place a variety of instruments and using radar to map the underside of the ice shelf and the bottom of the ocean. Penn State researchers did the geophysics for the project and the research team's results are reported today (Sept. 13) in Science.

The ice shelf is melting more rapidly from below for a number of reasons. The oceans are warmer than they have been in the past and water can transfer more heat than air. More importantly, the terrain beneath the ice shelf is a series of channels. The floating ice in the channel has ample room beneath it for ocean water to flow in. The water melts some of the ice beneath and cools. If the water remained in the channel, the water would eventually cool to a point where it was not melting much ice, but the channels allow the water to flow out to the open ocean and warmer water to flow in, again melting the ice shelf from beneath.

"The way the ocean water is melting the ice shelf is a deeply non-uniform way," said Anandakrishnan. "That's going to be more effective in breaking these ice shelves apart."

The breaking apart of the ice shelf in the channels is similar to removing an ice jam from a river. The shelf was plugging the channel, but once it is gone, the glacier moves more rapidly toward the sea, forming more ice shelf, but removing large amounts of ice from the glacier.

The melting of floating ice shelves does not contribute to sea level rise because once they are in the water, the ice shelves have already contributed to sea level rise. However, most of the Antarctic glaciers are on land, and rapidly adding new ice shelf material to the floating mass will increase sea level rise.

"Antarctica is relatively stable, but that won't last forever, said Anandakrishnan. "This is a harbinger of what will happen."

The researchers believe that the interaction of the ocean beneath the ice shelf and melting of the ice shelf is an important variable that should be incorporated into the sea level rise models of global warming. Other recent research shows that without the channelized underbelly of the ice shelf and glacier, melting would be even more rapid.

"The Antarctic has been relatively quiet as a contributor to sea rise," said Anandakrishnan. "What this work shows is that we have been blind to a huge phenomenon, something that will be as big a player in sea level rise in the next century as any other contributor."


Story Source:

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


Journal Reference:

  1. T. P. Stanton, W. J. Shaw, M. Truffer, H. F. J. Corr, L. E. Peters, K. L. Riverman, R. Bindschadler, D. M. Holland, and S. Anandakrishnan. Channelized Ice Melting in the Ocean Boundary Layer Beneath Pine Island Glacier, Antarctica. Science, 13 September 2013: 1236-1239 DOI: 10.1126/science.1239373

Cite This Page:

Penn State. "Underlying ocean melts ice shelf, speeds up glacier movement." ScienceDaily. ScienceDaily, 12 September 2013. <www.sciencedaily.com/releases/2013/09/130912143946.htm>.
Penn State. (2013, September 12). Underlying ocean melts ice shelf, speeds up glacier movement. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/2013/09/130912143946.htm
Penn State. "Underlying ocean melts ice shelf, speeds up glacier movement." ScienceDaily. www.sciencedaily.com/releases/2013/09/130912143946.htm (accessed November 24, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Monday, November 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

3D Map of Antarctic Sea Ice to Shed Light on Climate Change

3D Map of Antarctic Sea Ice to Shed Light on Climate Change

Reuters - Innovations Video Online (Nov. 24, 2014) A multinational group of scientists have released the first ever detailed, high-resolution 3-D maps of Antarctic sea ice. Using an underwater robot equipped with sonar, the researchers mapped the underside of a massive area of sea ice to gauge the impact of climate change. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Car Park Solution for Flexible Green Energy

Car Park Solution for Flexible Green Energy

Reuters - Innovations Video Online (Nov. 24, 2014) A British solar power start-up says that by covering millions of existing car park spaces around the UK with flexible solar panels, the country's power problems could be solved. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
NY Gov. on Flood Prep: 'prepared for the Worst'

NY Gov. on Flood Prep: 'prepared for the Worst'

AP (Nov. 23, 2014) First came the big storm. Now comes the big melt for residents of flood-prone areas around Buffalo. New York's governor says officials are preparing for the worst as the temperature is expected to rise and potentially melt several feet of snow. (Nov. 23) Video provided by AP
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