The Arctic ice layer is reducing at an amazing speed. (Photo: NOAA)
Arctic ice melting at record rates
Friday, August 24, 2012, 23:40 (GMT + 9)
The area of ice in the Arctic Ocean has been shrinking continually and now reached a record low that surpasses the previous 2007 minimum. This change strongly suggests that climate change is transforming the region, some scientific estimates stipulate.
"It is just below the 2007 minimum. We reached the minimum ice area today (Thursday). It has never been measured less than right now," elaborated Ola Johannessen, founding director of the Nansen Environmental and Remote Sensing Centre in Norway.
The melt is advancing at an unprecedented rate of more than 100,000 sqkm a day and there is currently at least a week of further melt expected before ice begins to refreeze as the northern winter approaches, the Guardian reports.
The summer thaw usually extends into September, and sea ice experts from the US National Snow and Ice Data Centre (NSIDC) have projected that the 2007 minimum extent will be exceeded next week.
"Unless something really unusual happens we will see the record broken in the next few days. It might happen this weekend, almost certainly next week," stated Julienne Stroeve, a scientist at NSIDC.
|Arctic sea ice area per 22. August 2012. (Graph: Nansen Center/www.arctic-roos.org)
At the same time, other scientists also checking on the ice are reading the satellite data in slightly differing ways, Reuters reports.
The Danish Meteorological Institute (DMI) compiled an ice chart showing the ice had also just shrunk a little past the 2007 minimum. The Institute said it would let the NSIDC judge when a record is reached.
Scientists posit that summer sea ice could be a thing of the past in the coming decades.
"This is due to climate change," affirmed Nicolai Kliem, head of the ice service at DMI.
As ice reflects sunlight back into space and as it melts it exposes the dark water underneath which in turn absorbs more heat and accelerates thawing, the ice melting may be self-reinforcing.
Johannessen underlined that his measurement was of the "area" of ice, now less than 4 million sqkm, and omits the open water flowing between ice floes.
In its measurements, the NSIDC prefers to embrace a bigger "extent", including water gaps, arguing that pools of meltwater that form on sea ice are hard to tell from open ocean.
Kliem said the ice was becoming more susceptible to melting because the poles now benefit from less of the hard, resilient ice that endures for more than one year. The ice usually reaches a minimum in September before re-solidifying as winter approaches and reaching a maximum thickness in March.
"We had quite a big ice cover in March 2012, above average. But because there is little long-term ice it melts more quickly in summer," he pointed out.
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By Natalia Real