Arctic Sea Ice Levels Boosted by a Third Due to a Cool Summer

First Posted: Jul 20, 2015 05:08 PM EDT

It turns out that the volume of Arctic sea ice increased by as much as a third after the summer of 2013. The unusually cool air temperatures prevented the ice from melting, which may mean that the ice pack in the Northern hemisphere is more susceptible to changes in summer melting than it is to winter cooling.

The new study used 88 million measurements of sea ice thickness recorded by the European Space Agency's CryoSat-2 mission between 2010 and 2014. It showed that there was a 14 percent reduction in the volume of summertime Arctic sea ice between 2010 and 2012, but the volume of ice jumped by 41 percent in 2014, relative to the previous year. This is when the summer was just 5 percent cooler than the previous year.

"The summer of 2013 was much cooler than recent years with temperatures typical of those seen in the late 1990s," said Rachel Tilling, lead author of the new study, in a news release. "This allowed thick sea ice to persist northwest of Greenland because there were fewer days when it could melt. Although models have suggested that the volume of Arctic sea ice is in long term decline, we know that it can recover by a significant amount if the melting season is cut short."

The volume of Arctic ice has been steadily falling since the late 1970s. But this decline has been difficult to assess accurately before CryoSat-2 was used. The new information, though, could be huge in terms of predicting ice loss in the future.

"Understanding what controls the amount of Arctic sea ice takes us one step closer to making reliable predictions of how long it will last, which is important because it is a key component of Earth's climate system," said Andy Shepherd, co-author of the new study.

The findings are published in the journal Nature Geoscience.