Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Significant contribution of Greenland's peripheral glaciers to sea-level rise

18.03.2013
The scientists looked at glaciers which behave independently from the ice sheet, despite having some physical connection to it, and those which are not connected at all.

The discovery, just published in Geophysical Research Letters, is important as it will help scientists improve the predictions of the future contribution of Greenland's ice to sea-level rise.


This is the Elephant Foot Glacier, NE-Greenland.
Credit: Dirk van AS (GEUS)


This is the Elephant Foot Glacier from space.
Credit: Landsat ETM; image editing: Tobias Bolch (University of Zurich)

Using lasers which measure the height of the ice from space, and a recently completed inventory of Greenland's glaciers and ice caps, scientists from the European-funded ice2sea programme, were able to determine changes in the mass of those ice bodies, separate from the main ice sheet.

It also showed that the contribution to sea-level rise from the glaciers of Greenland separated from the ice sheet makes up around 10% of the estimated contribution of the entire world's glaciers and ice caps, and that contribution is higher than expected.

Lead author Dr. Tobias Bolch, from the University of Zurich, says, "The melting of ice on Greenland is known to be one of the major sources for global sea-level rise. Beside the large ice sheet, there are thousands of peripheral glaciers which are not connected to the ice sheet or can be separated from it due to the existence of ice divides. The area of those glaciers is about 50 times higher than the ice cover of the European Alps. Consequently, it is important to investigate not only the ice sheet but also these local glaciers."

The paper, "Mass loss of Greenland's glaciers and ice caps 2003 - 2008 revealed from ICESat laser altimetry data", showed glaciers with no or weak connection to the main ice sheet contributed to around 30 Gigatons (Gt) of water per year to sea level between 2003 and 2008.

When they added in glaciers which had some link to the ice sheet, but which were still distinct from it in the way they flowed, this figure increased to up to around 50 Gt per year. This yearly figure represents more than half the water contained in one of Europe's largest lakes, Lake Geneva.

The study gives more detail to the make-up and stability of Greenland's glaciers showing that mass loss is highest in the warmer south east of the land mass and lowest in the colder north.

It also shows that the loss of ice is about 2.5 times higher for those separate glaciers than for the ice sheet, leading to the 15-20% figure.

Dr. Bolch says, "The other 80-85% comes from the ice sheet. The new figure for the local glaciers is higher than expected. It matters because the ice loss with respect to the area is significantly higher than of the ice sheet. This means that the local glaciers react faster with respect to climate change. This information will help to improve the predictions of the future contribution of Greenland's ice to sea-level rise."

A Gigaton (Gt) is the equivalent of 1 cubic kilometer (km3) of water. Lake Geneva contains about 90 km3 of water.

Literature:

T. Bolch, L. Sørensen, S. Simonssen, N. Mölg, H. Machguth, P. Rastner, F.,Paul. Mass loss of Greenland's glaciers and ice caps 2003-2008 revealed from ICESat data. Geophysical Research Letters, 40. March 15, 2013. doi: 10.1029/2012GL054710.

Contact:

Dr. Tobias Bolch
Department of Geography
University of Zurich
Phone +41 44 635 52 36
E-mail: tobias.bolch@geo.uzh.ch
For more information on ice2sea contact Paul B. Holland at the British Antarctic Survey Communications Office, Cambridge. Tel: +44 (0)1223 221226; Email: pbmho@bas.ac.uk.

Ice2sea brings together the EU's scientific and operational expertise from 24 leading institutions across Europe and beyond. Improved projections of the contribution of ice to sea-level rise produced by this major European-funded programme will inform the fifth IPCC report (due in 2013). In 2007, the fourth Intergovernmental Panel on Climate Change (IPCC) report highlighted ice-sheets as the most significant remaining uncertainty in projections of sea-level rise. Understanding about the crucial ice-sheet effects was "too limited to assess their likelihood or provide a best estimate of an upper bound for sea-level rise."

Dr. Tobias Bolch | EurekAlert!
Further information:
http://www.uzh.ch

More articles from Earth Sciences:

nachricht NASA sees quick development of Hurricane Dora
27.06.2017 | NASA/Goddard Space Flight Center

nachricht Collapse of the European ice sheet caused chaos
27.06.2017 | CAGE - Center for Arctic Gas Hydrate, Climate and Environment

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>