Spatio-temporal variability of sea-ice and ocean parameters over the Arctic Ocean in response to a warming climate

The fast receding sea-ice extent in the Arctic Ocean (AO) has implications for the global climate. Changes in the sea-ice dynamics cause variations in ocean physical and biogeochemical parameters. An ensemble of simulations from the 'Community Earth System Model' (CESM2-WACCM), part of the sixth phase of the Coupled Model Intercomparison Project (CMIP6), is utilized for years 1850-2100. The regional differences in sea-ice parameters are highlighted over seven marginal seas in the AO. The maximum difference in sea-ice heat content (similar to 4.5 x 10(8) J m(-2)) is obtained in the East Siberian Sea, central AO, and along the east coast of Greenland in March. The sea surface temperature has higher temporal variability in the Barents Sea, Beaufort Sea and Chukchi Sea in September, which confines the Fram Strait and the Barents Sea regions in March. In September, the sea-ice concentration shows large (>30%) temporal variations in the East Siberian Sea, Laptev Sea, Beaufort Sea, and along the coast of Greenland. Sea surface temperature is projected to increase by 6 degrees C over the Chukchi Sea by the year 2100. In response to sea-ice melting, a decline in sea-ice thickness and reduction of sea surface salinity up to 2.5 psu is observed in the future relative to the present in some parts of the AO. The advection of Atlantic water and its wind-driven mixing causes maximum winter-time warming in the Svalbard region over the eastern Greenland Sea. The future projections indicate the ice-free surface during September in the AO by the year 2050.