Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Greenland's ice loss accelerating rapidly, gravity-measuring satellites reveal

15.08.2006
A new analysis of data from twin satellites has revealed that the melting of Greenland's ice sheet has increased dramatically in the past few years, with much of the loss occurring primarily along one shoreline potentially affecting weather in Western Europe.

The loss of ice has been occurring about five times faster from Greenland's southeastern region in the past two years than in the previous year and a half. The dramatic changes were documented during a University of Texas at Austin study of Greenland's mass between 2002 and 2005.

The study was published today in the journal Science. Related results on the significant loss of ice from Antarctica were published in Science in March by other researchers participating in the Gravity Recovery and Climate Experiment (GRACE) mission. The GRACE mission is funded by NASA and the German Aerospace Center, and led by Aerospace Engineering Professor Byron Tapley at the university.

"Our latest GRACE findings are the most complete measurement of ice mass loss for Greenland," said Tapley, director of the university's Center for Space Research (CSR) and holder of the Clare Cockrell Williams Centennial Chair in Engineering. "The sobering thing to see is that the whole process of glacial melting is stepping up much more rapidly than before."

Antarctica is considered the largest, and Greenland the second largest, reservoir of fresh water on Earth, with the latter containing about 10 percent of the world's fresh water. Melting of ice from these two regions is expected to impact sea level and ocean circulation, and potentially the future of climates worldwide.

The Greenland study, for example, suggests that the amount of fresh water contributed from the melting of its ice sheet could add 0.56 millimeters annually to a global increase in sea levels, higher than all previously published measurements.

"These findings are consistent with the most recent independent measurements of Greenland's mass done by other techniques like satellite radar interferometry, but in this case they provide a direct measure of ice-mass changes," said Geology Professor Clark Wilson, a co-author on the latest Science article who helped analyze the estimates for Greenland. Wilson chairs the Department of Geological Sciences at the university and holds the Wallace E. Pratt Professorship in Geophysics.

Within the subpolar zone that includes Greenland, the rapid rise in meltwater along its eastern coast could add to other warming-related factors believed to be weakening the counterclockwise flow of the North Atlantic Current. For instance, the increased meltwater could change how more buoyant fresh water mixes with salt water in a branch of this flow called the Norwegian Current. This change could lower the temperatures of water, and thus wind, that travels past the west coast of Ireland and Great Britain.

That ocean temperature change would occur because the current might not move northward past Norway before returning to more southerly latitudes. Warmer, southerly waters would be stalled from moving northward if that happened, resulting in chillier winters in parts of Western Europe.

"If enough fresh water enters the Norwegian Current," Tapley said, "and you interrupt return flow, then there could be climate effects in Europe."

The twin GRACE satellites provide the most comprehensive monthly estimates of Greenland's ice-mass balance The satellites are sensitive to the gravitational pull of mass changes on Earth, which produce micrometer-scale variations in the distance (137 miles or 220 kilometers) that separates the two satellites as they fly in formation over Earth.

Lead author Jianli Chen, a CSR research scientist, developed a method to improve the effective spatial resolution of mass change estimates. The method used the known locations of major glaciers as information in estimating the sources of mass change.

"By using this special filtering procedure," Chen said, "we teased out additional details of mass changes in Greenland along its Southeastern and Northeastern shores separately."

The estimates showed that 69 percent of the ice-mass loss in recent years came from eastern Greenland. Of the 57 cubic miles (239 cubic kilometers) of water mass lost on average each year, 39 cubic miles (164 cubic kilometers) were from the eastern shoreline. More than half of that eastern loss involved ice from the glacier complex in southeast Greenland.

"This melting process may be approaching a point where it won't be centuries before Greenland's ice melts, but a much shorter time-frame," Tapley said, noting that it isn't possible to tell how much sooner this will be.

Tapley in the College of Engineering, and Wilson, whose department is part of the Jackson School of Geosciences, lead grants funded primarily by NASA to pursue research questions related to large-scale mass changes impacting Earth's features.

Becky Rische | EurekAlert!
Further information:
http://www.utexas.edu
http://www.engr.utexas.edu/news/action_shots/pages/GRACE_Tapley.cfm

More articles from Earth Sciences:

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

nachricht The melting ice makes the sea around Greenland less saline
16.10.2017 | Aarhus University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>