The large-scale Arctic sea ice and glacial melt impact the oceanic thermohaline structure, biogeochemistry, and atmospheric dynamics. The regional differences in the sea ice and its variability in the Arctic would, therefore, influence oceanic and atmospheric parameters and processes at different spatiotemporal scales contributing to the ?Arctic Ocean Amplification.? In the present study, we utilised a diagnostic model intercomparison project curated to assess sea-ice modeling named SIMIP as a part of the sixth phase of Coupled Model Intercomparison Project (CMIP6). Twelve CMIP6 models were selected based on their performance and availability of sea-ice parameters. The ensemble analysis of twelve climate models with multiple realisations shows regional differences in the sea-ice parameters within the Arctic and the inter-model bias, mainly over higher temporal variability regions. Trends in sea ice concentration, heat content, sea surface temperature, and sea surface salinity are calculated spatially over the Arctic and the seven area-averaged zones (marginal seas) in the Arctic Ocean. The maximum variability of SST (September) is seen over the Barents Sea, Beaufort Sea, and Chukchi Sea. Sea ice concentration has the highest variability in the East Siberian and Laptev Seas. However, the Beaufort Sea has a large variability due to sea ice drift. Surface freshening (up to 3 psu) of near-surface waters is noticed compared to past climate (historical). This freshening is attributed to the accelerated melting of sea ice and runoff through glacial melting. The mechanisms driving the regional differences in sea-ice concentration and thickness are explained using the heat content and budget analysis.
