Arctic Sea-Ice Growth is Lower Than Expected, Scientists Find
The Arctic may not be in good shape, data from a European satellite found.
While winter season is meant to bring about the growth of sea ice in the Arctic, it seems that it is not expanding as expected. The European Space Agency's (ESA) CryoSat satellite found that the Arctic has one of the lowest volumes of sea ice of any November, matching record low levels in 2011 and 2012.
Moreover, winter growth of ice in the Arctic has been 10 percent lower than usual, ESA said.
"Because CryoSat can measure Arctic sea ice thickness in autumn, it gives us a much clearer picture of how it has fared during summer," Rachel Tilling at the UK's Center for Polar Observation and Modelling (CPOM), said in a statement.
"Although sea ice usually grows rapidly after the minimum extent each September, this year's growth has been far slower than we'd expect - probably because this winter has been warmer than usual in the Arctic."
CryoSat's primary mission is to measure the thickness of polar sea ice and monitor the changes in the ice sheets that cover Greenland and Antarctica. It is equipped with a radar altimeter that measures the surface height variation of ice in fine detail, which allows scientists to accurately record changes in its volume. The observations are important for tracking climate change and are being used by maritime operators who navigate the icy waters of the polar regions.
According to the U.S. National Snow and Ice Data Center, the region in the Arctic covered by sea ice fell to 4.1 million sq km in September this year, which is less than the sea ice extent in September of 2011. But CryoSat shows that ice was thicker at an average of 116 cm at the end of the summer than in other years, which follows that there was more ice this year than in 2011.
The Arctic usually grows about 161 cubic km of ice per day in November, but this year it only gained 139 cubic km per day. Total ice volume is estimated to be 10,500 cubic km by the end of the month, which ties with that of November 2011.
Sea ice in the central Arctic is thicker than it was in 2011, but there is less ice in the southern regions of Beaufort, East Siberian and Kara Seas.
According to IFL Science, the slow growth of sea ice could be related to the anomalously warm temperatures in the northern region of the Arctic, where previous recordings found a temperature of -5 degrees Celsius in areas where the temperature at this time of year is expected to be as cold as -25 degrees Celsius.