Navigation Links
What is really happening to the Greenland icecap?
Date:11/3/2008

The Greenland ice cap has been a focal point of recent climate change research because it is much more exposed to immediate global warming than the larger Antarctic ice sheet. Yet while the southern Greenland ice cap has been melting, it is still not clear how much this is contributing to rising sea levels, and much further research is needed. A framework for such research was defined at a recent workshop organised by the European Science Foundation (ESF).

"The main objectives were to establish current understanding, prioritise research needs, and develop proposals," said one of the ESF workshop's convenors, Professor Tavi Murray from the Glaciology Group at Swansea University in the UK. "I believe we did the first two very well and laid the ground for developing research proposals."

While recent observations indicate that the Greenland ice cap is melting fast, it is uncertain how much this is contributing to sea levels, as co-convenor Carl Bggild, from UNIS in Svalbard explained. "A major challenge is to determine what fraction of melt water really runs off, because in many places the melt water will just drain into the cold snow and refreeze," said Bggild.

One way to determine how much water is running off is to measure not just the area of the Greenland ice cap but also its thickness, but this is much more difficult. Alternatively, the run off process can be tracked both on the ground and by satellite, preferably integrating the two, as was discussed at the workshop. The need to establish a database of ground based observations, including run off, as well as the ongoing calving of ice bergs from the ice cap and occasional events such as earthquakes beneath the ice was discussed.

Perhaps the greatest immediate challenge identified at the workshop though lies in reducing the high levels of uncertainty over the current and future behaviour of the Greenland ice cap, and reconciling the many conflicting observations and predictions. In the case of the meltwater, estimates of the annual total vary by a factor of five from 50 gigatons (GT) to around 250 GT, and this level of uncertainty makes future predictions almost meaningless. "Laser satellites can detect elevation changes within 10 cm accuracy - but do not consider compaction of the snow," said Murray. "Other satellites using radio waves have a problem with penetration of the signal into the snow. And, yet another method from satellites, measuring the 'weight' of the ice sheet covers too large areas - so you also detect weight changes outside the ice sheet." But at least these multiple sources of data have the potential of being combined to yield more accurate estimates.

Not surprisingly, given these uncertainties, it is unclear even what the immediate future holds for the Greenland ice cap. As Murray noted, recent high levels of thinning in the south and around the edges have taken climatologists by surprise, but there is no guarantee it will continue. "There is much uncertainty presently, because observations of thinning have come as a surprise," said Murray. "We can basically say that three scenarios are possible regarding the enhanced thinning which has been observed recently. One is that it will keep escalating. Secondly it may remain constant even though the climate gets warmer, and thirdly the enhanced rate of thinning may stop altogether, with future thinning being purely the result of melting."

It is not clear yet which of these scenarios will transpire, but Murray and Bggild are convinced that the ESF workshop has prepared the ground for substantial progress, by bringing together the relevant diverse skills in glaciology, climatology, geology, modelling and satellite imaging. The workshop, Sea-Level Rise From The Greenland Ice Sheet, was held in Mallorca, Spain in May 2008.


'/>"/>

Contact: Professor Tavi Murray
t.murray@swansea.ac.uk
44-017-926-02269
European Science Foundation
Source:Eurekalert

Related biology news :

1. For the birds or for me? Why do conservationists really help wildlife?
2. Hot peppers really do bring the heat
3. Early bird project really gets the worm
4. When is a stem cell not really a stem cell?
5. Greenland ice core reveals history of pollution in the Arctic
6. A survivor in Greenland: A novel bacterial species is found trapped in 120,000-year-old ice
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/8/2016)... -- Singulex, Inc., the leader in Next Generation Immunodiagnostics powered ... and supply agreement with Thermo Fisher Scientific, the world ... to Thermo Scientific BRAHMS PCT (Procalcitonin), a biomarker which, ... diagnose systemic bacterial infection and sepsis and in ... assessing the risk of critically ill patients for progression ...
(Date:12/7/2016)... BioCatch , the global leader in behavioral biometrics, reported ... to over 40 granted and pending patents. ... , The Company,s IP portfolio ... System, Device, and Method Estimating Force Applied to a Touch Surface, ... hardware components needed to estimate the force and pressure applied to touch ...
(Date:12/7/2016)... --  Veridium , a leader in biometrics-based authentication ... James Stickland . Stickland, a seasoned financial ... served in senior executive roles for HSBC, JPMorgan ... a pipeline of venture capital and accelerating innovation ... as managing director of U.K.-based fintech firm Red ...
Breaking Biology News(10 mins):
(Date:1/21/2017)... (PRWEB) , ... January 20, 2017 , ... ... consulting and resource to the healthcare industry ( http://www.gandlscientific.com ), has announced the ... expanding team of clinical and scientific consultants and contractors. This is the latest ...
(Date:1/21/2017)... PARSIPPANY, N.J. , Jan. 20, 2017 /PRNewswire/ ... the "Company"), a company that provides clinically useful ... that it has entered into a securities purchase ... aggregate of 855,000 shares of common stock in ... placement, the Company has agreed to sell to ...
(Date:1/21/2017)...   Boston Biomedical , an industry leader in ... stemness pathways, today presented data from two clinical studies ... American Society of Clinical Oncology (ASCO) Gastrointestinal Cancers Symposium ... In a Phase Ib/II study of napabucasin – ... stemness pathways by targeting STAT3 – colorectal cancer (CRC) ...
(Date:1/20/2017)... Ginkgo Bioworks, the organism company, announced ... the synthesis and assembly of DNA. The acquisition ... synthetic DNA into Ginkgo,s automated organism engineering foundries, ... of new organism designs for application across a ... founded to significantly increase the world,s capacity to ...
Breaking Biology Technology: