Measurements from ESA’s CryoSat satellite show that the volume of Arctic sea ice has significantly increased this autumn.

The volume of ice measured this autumn is about 50% higher compared to last year.

In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012.

Over the last few decades, satellites have shown a downward trend in the area of Arctic Ocean covered by ice. However, the actual volume of sea ice has proven difficult to determine because it moves around and so its thickness can change.

CryoSat was designed to measure sea-ice thickness across the entire Arctic Ocean, and has allowed scientists, for the first time, to monitor the overall change in volume accurately.

About 90% of the increase is due to growth of multiyear ice – which survives through more than one summer without melting – with only 10% growth of first year ice. Thick, multiyear ice indicates healthy Arctic sea-ice cover.

This year’s multiyear ice is now on average about 20%, or around 30 cm, thicker than last year.