Arctic sea ice is usually 1 to 3 meters, or as much as 9 feet thick.
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And retreating Arctic sea ice provides even more visible data to support conclusions of warming.
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Average monthly Arctic sea ice extent data shows a clear deceasing trend since 1979.
Local communities have been noticing profound changes in the Arctic sea ice environment for several decades.
The extent of Arctic sea ice extent fell to 4.10 million square kilometers on August 26, 2012.
The loss of Arctic sea ice is "big news", according to University of Alaska, Fairbanks, researcher Larry Hinzman.
"The time when Arctic sea ice is going to disappear is open to a lot of debate, " he said.
This past summer, the Arctic sea ice dwindled to its second lowest level.
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The Arctic sea ice area is expected to continue decreasing until September.
Each year, the Arctic sea ice reaches its minimum extent in September.
Charles pointed out that mankind had caused the Arctic sea ice to thin and rainforests to shrink by a third since the 1950s.
Ann Daniels from Whimple and Pen Hadow from Dartmoor will be studying the Arctic sea ice to help scientists understand more about climate change.
According to the National Snow and Ice Data Center, Arctic sea ice is melting faster than its average over the 1979 t0 2000 period.
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Arctic sea ice has been declining at a rate of 13% per decade since 1979, according to the National Snow and Ice Data Center.
Arctic sea ice cover grows each winter as the sun sets for several months, and shrinks each summer as the sun rises higher in the northern sky.
After the record low posted on August 26, Arctic sea ice levels continued to drop and is now below 4.00 million square kilometers (1.54 million square miles).
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Ocean levels are rising because Arctic sea ice is melting.
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As far as current global observations are concerned, Hansen cites both the decline of Arctic sea ice and the worldwide retreat of mountain glaciers as causes for major concern.
In the past decade, Arctic sea ice volumes have declined 36% during autumn and 9% during the winter, according to findings to be published in Geophysical Research Letters.
Today, the National Snow and Ice Data Center, in conjunction with NASA, announced today that Arctic sea ice has reached a record low since the previous record-breaking low in 2007.
"Such a loss of Arctic sea ice has recently been assessed to set in motion powerful climate feedbacks which will have an impact far beyond the Arctic itself, " Sommerkorn said.
Mechanisms on the verge of being instigated include loss of Arctic sea ice, shrinkage of the Greenland ice sheet, loss of Antarctic ice shelves, and shrinkage of the Antarctic ice sheets.
Weather stations, ocean measurements, decreases in snow cover, reductions in Arctic sea ice, longer growing seasons, balloon measurements, boreholes and satellites all show results consistent with the surface record of warming.
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They hypothesized that shrunken arctic sea ice at the end of summer meant that they had to swim over increasing distances to get to land, and, in a storm, they died of exertion.
And in February 2009 it was discovered that scientists had previously been underestimating the re-growth of Arctic sea ice by an area larger than the state of California (twice as large as New Zealand).
The Arctic sea ice is constantly moving, breaking open and reforming into different shapes - which means we can end up moving several kilometres in any direction while we are asleep in our tents.
Climate change models of Arctic sea ice cover in September, the month when ice is usually at its minimum, suggest an average loss of 2.5 percent of ice cover per decade from 1953 to 2003.
The rapid melting of the Arctic sea ice, then, illuminates the difficulty of modelling the climate but not in a way that brings much comfort to those who hope that fears about the future climate might prove exaggerated.
The year also saw Arctic sea ice hit a record low in more than 30 years of satellite observations and studies that found the world's major ice sheets have been shrinking at an increasing rate.
"This suggests that current model projections may in fact provide a conservative estimate of future Arctic change, and that the summer Arctic sea ice may disappear considerably earlier than IPCC projections, " said NSIDC's Julienne Stroeve who led the study.
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