Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Lakes beneath Antarctic ice sheets found to initiate and sustain flow of ice to ocean

22.02.2007
The Earth Institute at Columbia University—One of the planet's most remote and little-understood features may play a crucial role in transporting ice from the remote interior of Antarctica towards the surrounding ocean according to a new research.

Geophysicists Robin Bell and Michael Studinger from the Lamont-Doherty Earth Observatory, a part of The Earth Institute at Columbia University, led a team that discovered four large, subglaical lakes that for the first time the link these water bodies locked beneath miles of ice, to fast flowing ice streams in Antarctica. Together with colleagues from NASA, the University of New Hampshire and the University of Washington, the scientists found that, in four separate cases, lakes appear to contribute to the formation of ice streams. Their work appears in the February 22 issue of the journal Nature.

Ice streams are large, fast-flowing features within ice sheets that transport land-based ice and meltwater to the ocean. One such stream, the Recovery Ice Stream, drains 8 percent of the U.S.-sized East Antarctic Ice Sheet. The Recovery basin, unexplored since 1966, funnels an estimated 35 billion tons of ice into the Weddell Sea annually.

"Until about a year ago, not many people cared much about subglacial lakes," said Studinger. "That's changing, but we're still only just beginning to understand how these lakes, sealed beneath more than two miles of ice, have the potential to impact the rest of the world."

The scientists examined satellite radar images and high-resolution laser profiles of the region for ice stream patterns and surface features indicating the presence of subglacial lakes beneath the ice. Not only did they find four new lakes, but they discovered that the lakes coincide with the origin of tributaries of the Recovery Glacier. Upstream of the lakes, the ice sheet moves at just 2 to 3 meters per year; downstream the flow increases to nearly 50 meters per year. Bell and Studinger conclude that the lakes provide a reservoir of water that lubricates the bed of the stream to facilitate ice flow and prevent the base of the sheet from freezing to the bedrock.

Moreover, their work suggests that subglacial lakes could play a role in and sea level rise as well as regional and global climate change. Meltwater at the base of ice streams increases the flow of ice to the oceans, which could, in turn, contribute to higher sea levels worldwide. In addition, floods have been known to originate from the interior of the ice sheet in the past, possibly from subglacial lakes. These sudden pulses of fresh water could potentially interfere with nearby ocean currents that redistribute heat and carbon dioxide around the globe, disrupting the Earth's finely tuned climate system.

"It's almost as if the lakes are capturing the geothermal energy from the entire basin and releasing it to the ice stream." said Bell. "They power the engines that drive ice sheet collapse. The more we learn about them, the more we realize how important they are."

Clare Oh | EurekAlert!
Further information:
http://www.ei.columbia.edu

More articles from Earth Sciences:

nachricht Algorithm provides early warning system for tracking groundwater contamination
14.08.2018 | DOE/Lawrence Berkeley National Laboratory

nachricht Artificial Glaciers in Response to Climate Change?
10.08.2018 | Universität Heidelberg

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

'Building up' stretchable electronics to be as multipurpose as your smartphone

14.08.2018 | Information Technology

During HIV infection, antibody can block B cells from fighting pathogens

14.08.2018 | Life Sciences

First study on physical properties of giant cancer cells may inform new treatments

14.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>