Monthly January ice extent for 1979 to 2016 shows a decline of 3.2 percent per decade. The monthly average January 2016 sea ice extent was the lowest in the satellite record. Graphic: National Snow and Ice Data Center

By Yereth Rosen
5 February 2016

(Alaska Dispatch News) – Sea ice extent over the Arctic last month was the lowest for any January in the satellite record, with freeze-up slowed by unusually high air temperatures over the Arctic Ocean and an atmospheric pattern in the Atlantic side that moved cold weather to more southern latitudes, scientists said.

The National Snow and Ice Data Center in Colorado reported that sea ice extent averaged 5.2 million square miles in January, about 7.1 percent below the 1981-2010 average and about 35,000 square miles lower than the previous record January low, which was set in 2011.

The low ice extent was tied directly to unusual weather in the far north.

“We had a January that was just absurdly warm over the Arctic Ocean,” said Mark Serreze, the center's director.

That was partly the result of a negative turn in the Arctic Oscillation, a pattern that weakened the atmospheric barrier between the polar latitudes and the mid-latitudes, with possible contributions from the powerful El Nino system that is affecting the Pacific coast, Serreze said.

“There’s a lot of things conspiring at once right now,” Serreze said.

January ice extent was particularly low in the Barents Sea, Kara Sea and the East Greenland Sea on the Atlantic side of the Arctic, but also low in the Bering Sea and Sea of Okhotsk, the center reported. [more]

Arctic sea ice hit record low for January


Arctic sea ice extent as of 3 February 2016, along with daily ice extent data for four previous years. 2015 to 2016 is shown in blue, 2014 to 2015 in green, 2013 to 2014 in orange, 2012 to 2011 in brown, and 2011 to 2012 in purple. The 1981 to 2010 average is in dark gray. The gray area around the average line shows the two standard deviation range of the data. In January 2016, Arctic sea ice extent was the lowest in the satellite record. Graphic: National Snow and Ice Data Center

4 February 2016 (NSIDC) – January Arctic sea ice extent was the lowest in the satellite record, attended by unusually high air temperatures over the Arctic Ocean and a strong negative phase of the Arctic Oscillation (AO) for the first three weeks of the month. Meanwhile in the Antarctic, this year’s extent was lower than average for January, in contrast to the record high extents in January 2015.

Overview of conditions

Arctic sea ice extent during January averaged 13.53 million square kilometers (5.2 million square miles), which is 1.04 million square kilometers (402,000 square miles) below the 1981 to 2010 average. This was the lowest January extent in the satellite record, 90,000 square kilometers (35,000 square miles) below the previous record January low that occurred in 2011. This was largely driven by unusually low ice coverage in the Barents Sea, Kara Sea, and the East Greenland Sea on the Atlantic side, and below average conditions in the Bering Sea and Sea of Okhotsk. Ice conditions were near average in Baffin Bay, the Labrador Sea and Hudson Bay. There was also less ice than usual in the Gulf of St. Lawrence, an important habitat for harp seals.

January 2016 was a remarkably warm month. Air temperatures at the 925 hPa level were more than 6 degrees Celsius (13 degrees Fahrenheit) above average across most of the Arctic Ocean. These unusually high air temperatures are likely related to the behavior of the AO. While the AO was in a positive phase for most of the autumn and early winter, it turned strongly negative beginning in January. By mid-January, the index reached nearly -5 sigma or five standard deviations below average. The AO then shifted back to positive during the last week of January. (See the graph at the NOAA Climate Prediction Web site.)

The sea level pressure pattern during January, which featured higher than average pressure over northern central Siberia into the Barents and Kara sea regions, and lower than average pressure in the northern North Pacific and northern North Atlantic regions, is fairly typical of the negative phase of the AO. Much of the focus by climate scientists this winter has been on the strong El Niño. However, in the Arctic, the AO is a bigger player and its influence often spills out into the mid-latitudes during winter by allowing cold air outbreaks. How the AO and El Niño may be linked remains an active area of research.

January 2016 compared to previous years

The monthly average January 2016 sea ice extent was the lowest in the satellite record, 90,000 square kilometers (35,000 square miles) below the previous record low in 2011. The next lowest extent was in 2006. Interestingly, while 2006 and 2011 did not reach record summer lows, they both preceded years that did, though this may well be simply coincidence.

The trend for January is now -3.2% per decade. January 2016 continues a streak that began in 2005 where every January monthly extent has been less than 14.25 million square kilometers (5.50 million square miles). In contrast, before 2005 (1979 through 2004), every January extent was above 14.25 million square kilometers. [more]

January hits new record low in the Arctic

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