Only small stretches of water remained open to navigation

Nov 8, 2013 13:53 GMT  ·  By
Arctic sea ice extent for October 2013 was 8.10 million square kilometers (3.13 million square miles)
   Arctic sea ice extent for October 2013 was 8.10 million square kilometers (3.13 million square miles)

According to a monthly report for October, the Arctic Ocean is almost entirely frozen over. Scientists with the US National Snow and Ice Data Center (NSIDC) say that the open stretches of water that were left behind go a long way towards explaining the warmer average temperatures that were recorded last month over and around the North Pole. 

Clear waters were observed in the Kara, Beaufort, and Chukchi seas. These spans were considerably darker in color than the surrounding ice, meaning that they were able to absorb more solar radiation, and thus become warmer.

Overall, sea-ice extents continued to increase, following a trend set in September, when the minimum ice extent for 2013 was reached. From October 1 to the end of the month, the Arctic gained around 3.21 million square kilometers (1.24 million square miles) of new ice.

According to the latest NSIDC report, the average ice extent throughout the North Pole was 8.10 million square kilometers (3.13 million square miles), making it the sixth smallest ever recorded. The values were calculated against the average extents recorded between 1981 to 2010.

Experts determined that Arctic sea ices recovered at a rate of about 103,500 square kilometers (40,000 square miles) per day throughout last month. These values were significantly higher than in 2012, where many areas of the ocean remained ice-free until mid-October.

“In October, air temperatures along the coastal Beaufort Sea were 6 to 8 degrees Celsius (11 to 14 degrees Fahrenheit) higher than average,” NSIDC investigators wrote in their latest report.

“Air temperatures were also 2 to 4 degrees Celsius (4 to 7 degrees Fahrenheit) higher than average over much of the western and central Arctic and near Greenland and the Canadian Archipelago,” they add.

Last month also marked the first time since 2009 when October sea-ice extents exceed 8 million square kilometers (3.09 million miles). Experts say that the other instance when this happened over the past decade was in 2006.

As a direct result of the warmer-than-average temperatures, the Arctic tundra has again increased in size and has remained greener throughout the autumn months. Overall, the trend plants exhibit towards larger overall size is making itself even more apparent.