Recent news of the return of some of the sea ice extent in the Arctic has been met with jubilation by many in the media. This has sparked a conversation amongst those who believe that the climate is cooling, and that the warnings of global warming and climate change are unfounded. As a result, some have suggested that we should celebrate this cooling trend and put aside our concerns about human-caused global warming, such as emissions from fossil fuels. This sentiment has been so strong that some have even called for Al Gore to return his Oscar.
Here’s some of the good news:
“Good News for Polar Bears! The Arctic Ice Pack is 60 Per Cent BIGGER than it was a Year Ago,” The Sun, Sept. 8, 2013.
“And now it’s Global COOLING! Record Return of Arctic Ice Cap as it Grows by 60% in a Year,” Mail Online, Sept. 7, 2013.
“Global Warming? No, Actually We’re Cooling, Claim Scientists,” The Telegraph, Sept. 8, 2013.
Recent reports from the National Snow & Ice Data Center (NSIDC) show that Arctic sea ice extent has been in decline for the past 35 years. This year (2013) saw a slight increase in sea ice extent, but this blip was considerably slower than the record decline rate in August 2012. The August 2013 extent was the sixth lowest in the 1979 to 2013 satellite record.
NSIDC’s Overview of Conditions states that sea ice extent for August 2013 averaged 6.09 million square kilometers (2.35 million square miles). This was 1.03 million square kilometers (398,000 square miles) below the 1981 to 2010 average for August, but well above the level recorded last year.
The cooling crowd may be celebrating a cooling cycle, but the long-term trend remains solidly down. The real scientific measurement of Arctic sea ice is volume, which is a three-dimensional measurement. This tells us how much ice really exists, rather than how much of the sea is covered by a thin layer of ice, which comes and goes with changing weather patterns.
Ice Mass Balance Buoys deployed in multi-year ice before the melt season began showed surface ice melting ranging from zero in the central Arctic to 30 inches of melt in the Beaufort Sea area. Bottom melting of the ice sheet varied from 3-to-43 inches, with the largest melt thinning from 133 inches (June) down to 62 inches on August 28th near the ice edge in the Beaufort Sea. Ice thickness loss at other buoys on August 28th ranged from 48-to-105 inches.
The results of these readings show that considerably more multi-year sea ice was lost in 2013, despite the slight increase in sea ice extent. It is clear that Arctic sea ice continues to lose volume year after year, and that the cooling crowd’s celebrations are premature.
