Arctic sea ice rebound shows resilience

Arctic sea ice levels have declined about 40 percent since the late 1970s, a fact which has stoked environmentalist fears about habitat loss for polar animals and for indigenous peoples living in the region.

When compared to ~772,000 readings from an airborne laser, 430 measurements from electromagnetic sensors and 80 million upward-looking sonar observations, the team found that CryoSat’s measurements of sea ice thickness agreed to within 2mm.

The rapidly melting region increased its volume by a third, figures reveal, as temperatures dropped dramatically for the first time since the 1990s.

The research is significant as it shows the Arctic ice cap may be more resilient than expected.

Arctic sea ice extent for this year, while off to a rough start, is now tracking at near normal levels, according to the National Snow and Ice Data Center – based on the 1981 to 2010 average. And in 2014 there was 25% more sea ice, offsetting some of the losses recorded in the previous years.

Satellite data shows a relatively cool summer in 2013 caused a boom in sea ice volume for the next two autumns. This information is essential for working out the thickness of the ice and how it is changing and, ultimately, how the volume of Earth’s ice is being affected by the climate. Now there’s way more Arctic sea ice (and ice that’s thicker) than was present during 2012 – a year that saw extremely low sea ice extent and ice volume.

“The long-term trend of the ice volume is downwards and the long-term trend of the temperatures in the Arctic is upwards and this finding doesn’t give us any reason to disbelieve that – as far as we can tell it’s just one anomalous year”, Tilling reassured the Beeb. “It shows there is hope for Arctic sea ice, if you can turn the clock back to colder temperatures, which would need huge reductions in carbon emissions”.

“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”, study co-author Andy Shepherd, a professor of earth observation at UCL and at the University of Leeds, said in the release.

‘Our goal is to make sure we do not lose this unique capability to monitor Arctic sea ice when the mission ends.’.

The team now plan to use CryoSat-2’s measurements of changing sea ice thickness to help improve the models that are used to predict future climate change, and also to assist maritime activities in the Arctic region, which can be risky and costly to navigate.