Rising temperatures in the Arctic during the last winter in the northern hemisphere caused the ice sheet reached lower maximum area on record this season.
In 2016, the maximum ice cover, registered on 24 March, was 14.52 million square kilometers, beating the lower record last year, which had been 14.54 million square kilometers.
These measures relate to the maximum ice coverage area in the sea before she started to retreat with the arrival of spring.
The Arctic warming
"The lower record of the Arctic ice cap, during the last winter, is one of the symptoms and consequences of global warming underway, caused by human emissions of greenhouse gases," says the scientist Stefan Rahmstorf, of the Potsdam Institute for Research for Climate Impact.
He recalls that global temperatures have increased steadily since the early 1970's air temperatures over the Arctic in December, January and February were between 2 and 6 degrees Celsius above average in almost all regions, according to the National Center snow and US Ice (NSIDC, its acronym in English).
Temperatures of 12 degrees Celsius above the average were recorded in the north of Svalbard in March. "I had not seen a winter as warm and wacky in the Arctic," says Mark Serreze, director of the NSIDC. "The heat was relentless."
On March 24, the extent of sea ice in the sea was 14.52 million square kilometers
warm Atlantic waters
According to scientists, the high temperatures may have been caused in part by the effect of El Niño in the Pacific Ocean. The most dramatic thaw, however, was on the side nearest the Arctic to the Atlantic, in the seas of Barents and Kara.
Tore Furevik, director of the Bjerknes Centre for Climate Research in Norway, he said that this was because the warm currents of the Atlantic are the main causes of melting sea during winter.
"We had very hot water flowing into the Arctic, coming from the North Atlantic during the past few years," explains Furevik. "Part of it is probably global warming guilt, but another part may be due to natural fluctuations."
Therefore, the ice at sea during winter is seen as a less reliable indicator of climate change than the ice during the summer. But Furevik said that climate change was undoubtedly an important factor.
"We had a record melt in the Arctic last year and a new record this year - this points to global warming should not be surprised if, next year, we have again more ice, but the long-term trend is evidently. less sea ice, "says the expert.
Implications for weather systems
The loss of ice in the Arctic and the consequent rise in sea level have implications for weather systems. "What raises particular
concern is the rapid Arctic warming during the last 15 years, "says Rahmstorf.
"This has caused an accelerated loss of continental ice in Greenland, which raises sea levels and probably contributes to the weakening of the Gulf Stream. Possibly also affected the jet streams in the atmosphere and has been associated with extreme weather events in latitudes medium ", highlights.
Less ice in the sea means that more heat can be absorbed and emitted by the ocean. Furevik says that surveys were being conducted to list the possible impacts of the thaw in the Barents Sea to the east the climate systems, including consequences for winter from countries like China and Japan.
Boost for fishing
However, there are those who win with the North Atlantic warming. A lower layer of ice and warmer waters have been a considerable boost for fishing, says Furevik.
"The amount of cod in the northern coast of Norway and the Barents Sea seems to be bigger than ever. So it's a very positive impact for the northern Norwegian economy," he explains.
However, Greenpeace warned that fishing in the Arctic poses a threat to the region's biodiversity.
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