Variability of Arctic Sea Ice (1979-2016)

This study is based on the daily sea ice concentration data from the National Snow and Ice Data Center (NSIDC; Cooperative Institute for Research in Environmental Sciences (CIRES), Boulder, CO, USA) from 1979 to 2016. The Arctic sea ice is analyzed from the total sea ice area, first year ice extent, multiyear ice area, and the variability of sea ice concentration in different ranges. The results show that the total sea ice area decreased by 0.0453 x 10(6) km(2)year(-1) (-0.55%/year) between 1979 and 2016, and the variability of the sea ice area from 1997 to 2016 is significantly larger than that from 1979 to 1996. The first-year ice extent increased by 0.0199 x 10(6) km(2)year(-1) (0.36%/year) from 1997 to 2016. The multiyear ice area decreased by 0.0711 x 10(6) km(2)year(-1) (-0.66%/year) from 1979 to 2016, of which in the last 20 years is about 30.8% less than in 1979-1996. In terms of concentration, we have focused on comparing 1979-1996 and 1997-2016 in different ranges. Sea ice concentration between 0.9-1 accounted for about 39.57% from 1979 to 1996, while from 1997-2016, it accounted for only 27.75%. However, the sea ice of concentration between 0.15-0.4 exhibits no significant trend changes.