Greenlandic ice flow causing substantial sea-level rise
Along with surface melting, iceberg calving into the ocean also contribute considerably to sea-level rise. The new model by Iranian researcher Faezeh Nick (Utrecht University) now provides much better insight into the future behaviour of large outlet glaciers in Greenland. The model reveals that the sea level will rise 4 to 9 cm by 2100 due to glacier dynamic alone. Together with colleagues from abroad, the Utrecht scientists are presenting their conclusions in the scientific journal Nature on 9 May.
Due to climate change, ice loss from the Greenland ice sheet and other glaciers has been accelerating. There are two possible causes of ice mass loss: the ice is melting (a great deal is known about this), and the glacier ice is flowing into the ocean. Until now, describing the latter process has been a problem for researchers. But now, by using her new model, climate researcher Faezeh Nick is able to quantify the ice flow of the Greenlandic outlet glaciers.
Greater share than expected
“The model shows that, as a result of the ice flow, Greenland’s total contribution to sea-level rise is 4 to 9 cm by 2100”, says Nick. “That is almost half of the total mass loss from Greenland. In particular, this means the lower limit of Greenland’s contribution is higher than the previous estimates.”
Features of the new model
“The most significant advantage of the new model is that it is able to simulate the current behaviour of outlet glaciers”, says Nick. The flow velocity of glaciers is affected by icebergs breaking off. The model considers how warmer atmosphere and ocean affect the glacier flow and calving, and how the shape of the ground beneath the ice controls the behaviour of the glacier.
Unique for the Netherlands
This research is a unique achievement by this young Iranian researcher, who has now been working in the Netherlands for ten years. Faezeh wrote this article on Greenland’s four major glaciers together with scientists from the Netherlands, Switzerland, England, Denmark, America and Belgium.
Contribution to climate report
A new climate report is being published this autumn in which the contribution of the ice flow is being explicitly included for the first time, partly based on this article.
‘Future sea-level rise from Greenland’s major outlet glaciers in a warming climate’, Faezeh Nick and Roderik van de Wal, et al., Nature, 9 May 2013.
This research was made possible financially by the University of Utrecht, NWO the Knowledge for Climate programme, and by the EU funded programme Ice2sea.
Article in Trouw (in Dutch)