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 Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie

nachricht Modeling magma to find copper
13.01.2017 | Université de Genève

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>