Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

2010 spike in Greenland ice loss lifted bedrock, GPS reveals

09.12.2011
An unusually hot melting season in 2010 accelerated ice loss in southern Greenland by 100 billion tons – and large portions of the island’s bedrock rose an additional quarter of an inch in response.

That’s the finding from a network of nearly 50 GPS stations planted along the Greenland coast to measure the bedrock’s natural response to the ever-diminishing weight of ice above it.

Every year as the Greenland Ice Sheet melts, the rocky coast rises, explained Michael Bevis, Ohio Eminent Scholar in Geodynamics and professor in the School of Earth Sciences at Ohio State University. Some GPS stations around Greenland routinely detect uplift of 15 mm (0.59 inches) or more, year after year. But a temperature spike in 2010 lifted the bedrock a detectably higher amount over a short five-month period – as high as 20 mm (0.79 inches) in some locations.

In a presentation Friday at the American Geophysical Union meeting in San Francisco, Bevis described the study’s implications for climate change.

“Pulses of extra melting and uplift imply that we’ll experience pulses of extra sea level rise,” he said. “The process is not really a steady process.”

Because the solid earth is elastic, Bevis and his team can use the natural flexure of the Greenland bedrock to measure the weight of the ice sheet, just like the compression of a spring in a bathroom scale measures the weight of the person standing on it.

Bevis is the principal investigator for the Greenland GPS Network (GNET), and he’s confident that the anomalous 2010 uplift that GNET detected is due to anomalous ice loss during 2010: “Really, there is no other explanation. The uplift anomaly correlates with maps of the 2010 melting day anomaly. In locations where there were many extra days of melting in 2010, the uplift anomaly is highest.”

In scientific parlance, a melting day “anomaly” refers to the number of extra melting days – that is, days that were warm enough to melt ice – relative to the average number of melting days per year over several decades.

In 2010, the southern half of Greenland lost an extra 100 billion tons of ice under conditions that scientists would consider anomalously warm.

GNET measurements indicate that as that ice melted away, the bedrock beneath it rose. The amount of uplift differed from station to station, depending on how close the station was to regions where ice loss was greatest.

Southern Greenland stations that were very close to zones of heavy ice loss rose as much as 20 mm (about 0.79 inches) over the five months. Even stations that were located far away typically rose at least 5 mm (0.2 inches) during the course of the 2010 melting season. But stations in the North of Greenland barely moved at all.

From 2007 to 2009, GNET installed GPS stations in the bedrock that lay exposed around the ice sheet margins along the Greenland coast. The research team is using the earth’s natural elasticity of to “weigh” the ice. As previous Ohio State studies of Antarctica revealed, ice weighs down bedrock, and when the ice melts away, the bedrock rises measurably in response.

GNET and similar GPS networks around the world could thus allow scientists to continue to measure ice loss after the Gravity Recovery and Climate Experiment (GRACE) satellites are retired in 2015. (GRACE is a joint project of NASA and the German Aerospace Center.)

Bevis’ coauthors in the School of Earth Sciences at Ohio State include Abel K. Brown, Eric C. Kendrick, Jason E. Box, Dana John Caccamise, Hao Zhou, Jian Wang, and Terry J. Wilson.

Their colleagues include John M. Wahr of the University of Colorado, Boulder; Shfaqat Abbas Khan, Finn Bo Madsen, and Per Knudsen of the Danish Technical University in Copenhagen; Michael J Willis of Cornell University; Tonie M. van Dam and Olivier Francis of the University of Luxembourg; Bjorn Johns, Thomas Nylen, and Seth White of UNAVCO, Inc, in Boulder; Robin Abbott of CH2M HILL Polar Services, in Boulder; and Rene Forsberg of the Space Institute, Denmark.

GNET is funded by the National Science Foundation.

Contact: Michael Bevis, (614) 247-5071; Bevis.6@osu.edu
Written by Pam Frost Gorder, (614) 292-9475; Gorder.1@osu.edu

Michael Bevis | EurekAlert!
Further information:
http://www.osu.edu

More articles from Earth Sciences:

nachricht Clear as mud: Desiccation cracks help reveal the shape of water on Mars
20.04.2018 | Geological Society of America

nachricht Hurricane Harvey: Dutch-Texan research shows most fatalities occurred outside flood zones
19.04.2018 | European Geosciences Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>