UXBRIDGE, Canada - The world's northern freezer is on rapid defrost as large volumes of warm water are pouring into the Arctic Ocean, speeding the melt of sea ice, according to a new study.
The world's northern freezer is on rapid defrost as large volumes of warm water are pouring into the Arctic Ocean, speeding the melt of sea ice, according to a new study. (NASA Goddard Photo)
Surface temperatures in parts of the Arctic have been 21 degrees C above normal for more than a month in recent weeks.
"Boats were still in the water during the first week of January," said David Phillips, a senior climatologist with Environment Canada, referring to southern Baffin Island, some 2,000 km north of Montreal. This is a region that receives just four or five hours of weak sunlight during the long winter. Temperatures normally range from -25 to -35 degrees C but were above zero on some days in January.
"It's impossible for many people in parts of the eastern Arctic to safely get on the ice to hunt much-needed food for their families - for the second winter in a row," Phillips said in a report.
The warming and melting of the Arctic is happening much faster than expected and new data reveals that huge volumes of warmer water from the North Atlantic are now flowing into and warming up the Arctic Ocean, researchers reported Friday in the journal Science.
"In the past hundred years the waters in the Fram Strait have warmed about two degrees C," says co-author Thomas Marchitto, of Colorado University's Institute of Arctic and Alpine Research.
The Fram Strait between Greenland and Svalbard (Spitsbergen) is the major connection between the Arctic Ocean and the world ocean. An international team of researchers analysed marine sediments and found that temperatures of the northward inflowing Atlantic water varied by just a few tenths of a degree Celsius during the past 2,000 years. However, in the last hundred years temperatures have shot up by two degrees C.
"What's happening here is very unusual compared to the last 2,000 years," Marchitto told IPS.
Climate change is believed to be behind this warmer water because over 90 percent of additional heat trapped in the atmosphere from the burning of fossil fuels like coal, oil and natural gas is going into the oceans, he said.
"The accelerated decrease of the Arctic sea ice cover and the warming of ocean and atmosphere in the Arctic, as measured during the past decades, are in part related to an increased heat transfer from the Atlantic," said co-author Robert Spielhagen, a palaeoceanographer at the Academy of Sciences, Humanities and Literature in Mainz, Germany.
Sea ice has declined dramatically during the short Arctic summers in recent years, with some experts now projecting that the ice cover will be essentially gone in as little as five years. Just a few years ago, no one thought a summer ice-free Arctic could happen before 2060.
The warming Arctic and melting sea ice is a planetary-scale change since the Arctic Ocean covers 14 million sq km, an area almost as big as Russia. The Arctic and Antarctic polar regions are key drivers of Earth's weather and climate. The rapid defrosting of the Arctic has already altered the climate system, researchers now agree.
IPS previously broke the story revealing that the snow and cold in the eastern United States and Europe during the winter of 2009-10 was likely the result of the loss of Arctic sea ice. The same thing has happened this year.
As more and more sea ice melts, there is more open water to absorb the summer sun's heat. A day of 24-hour summer sun in the Arctic puts more heat on the surface of the ocean than a day in the tropics, James Overland of the NOAA/Pacific Marine Environmental Laboratory in the United States told IPS.
That extra heat in the ocean is gradually released into the lower atmosphere from October to January as the region slowly re-freezes months later than normal. This is a fundamental change - a large part of the Arctic Ocean is radiating heat instead of being cold and ice-covered. That has disrupted wind circulation patterns in the northern hemisphere, reported Overland and other researchers at the International Polar Year Oslo Science Conference in Norway last June.
The result: the Arctic stays warm and mid-latitude regions become colder and receive more snow for much of the winter. Last December was the coldest south Florida has experienced in more than a century of record-keeping.
Most of Britain suffered through its coldest December ever. Up in the Arctic, Coral Harbour on the northwest corner of Hudson Bay was above zero degrees C for two days in early January for the first time in history. Much of the eastern Arctic centred around Baffin Island averaged +21C above normal between Dec. 17 and Jan. 15 this year.
This looks to be the new normal since Arctic experts agree the melting sea ice is now locked into a death spiral.
"In future, cold and snowy winters will be the rule rather than the exception" in the eastern United States and Europe, Overland previously told IPS.
This week the U.S. northeast suffered through its sixth major snowstorm this winter, breaking all snowfall records.
Copyright © 2011 IPS-Inter Press Service
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