The Arctic usually gains about 161 cubic km of ice per day in November, but this year’s growth has been about 10% lower, at 139 cubic km per day, with a total ice volume estimated to have accumulated to 10 500 cubic km by the end of the month. But CryoSat shows that the ice was thicker at the end of summer than in most other years, at 116 cm on average. This means there was substantially more ice this year than in 2011. Thicker ice can occur if melting is lower, or if snowfall or ice compaction is higher. Via esa.int