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Iceland鈥檚 glaciers are melting more slowly than expected because they are close to a 鈥渃ool blob鈥� of water in the North Atlantic Ocean.

at Utrecht University in the Netherlands and his colleagues devised a model to reconstruct the shrinking of Iceland鈥檚 glaciers between 1958 and the present day. The model was based on regional data from the surrounding North Atlantic, as well as atmospheric data and information from the glaciers themselves.

The team then used this information to predict what will happen to the country鈥檚 glaciers between now and 2100.

The researchers found that Iceland鈥檚 glaciers 鈥� which cover about 10 per cent of the country 鈥� started melting more quickly around 1995. But, in agreement with previously published work, they discovered that this rate of loss slowed after 2011.

鈥淲e already knew Iceland鈥檚 glaciers were melting slower from satellites, but with this model, we could link this to the development of a cool blob in the ocean,鈥� says No毛l.

This 鈥渃ool blob鈥� is a spot in the North Atlantic, just south of Greenland, which is particularly cold. 鈥淲e don鈥檛 have conclusive evidence for what caused this blob or how big it really is as it鈥檚 always fluctuating,鈥� says No毛l.

The team estimates that before 2011, Iceland was losing about 11 gigatonnes of ice a year, whereas after this date, the losses have been about half this figure.

The researchers鈥� model predicts that the blob will keep cooling Iceland鈥檚 glaciers until about 2050, when it will dissipate. At this point, the glaciers will start melting more quickly again. 鈥淏y the end of the 21st century, these glaciers will have lost a third of their total volume,鈥� says No毛l.

Moreover, by 2100, the glaciers will have lost the same amount of volume as they would have done regardless of whether the cool blob in the North Atlantic existed or not, according to the model.

But No毛l adds that this model doesn鈥檛 consider additional warming effects or feedback loops generated by ice melting in the first place. 鈥淪o this speed of melting could be even worse,鈥� he says.

The key to slowing the rate of loss is curbing climate change. 鈥淚f we stop warming so much in the second half of the century, then we can conserve these glaciers for longer,鈥� he says.

鈥淭his is a significant paper which shows that against the backdrop of long-term global warming and greater than average warming in the Arctic, short-term regional cooling鈥� can actually reduce the amount by which the glaciers in Iceland shrink,鈥� says at the Scott Polar Research Institute at the University of Cambridge.

Willis thinks that the cool blob is probably caused by the warming of the Arctic, which has led to cold fresh water from melting ice entering the North Atlantic Ocean.