Assessments of the Arctic amplification and the changes in the Arctic sea surface

Although dramatic warming is occurring in the Arctic, it is incomplete to provide an estimate to the Arctic Amplification (AA) based only on the surface air temperature (SAT) obtained at a few land stations. In this study, a comprehensive evaluation has been made with sea surface temperature (SST) and SAT from the Arctic land and ocean. Additionally, the variations of sea surface parameters were analyzed for a better understanding of the updated Arctic changes in recent years. AA was underestimated by 4.3% when only considering the SAT. During 1982–2018, the Arctic and global SSTs increased dramatically after 2002 with a near-synchronous trend in 2011–2018. Sea ice extent exhibited negative anomalies in September and March after 2002, which were more significant in September. The warming was more remarkable in March than that in September, and the negative SST anomaly entirely disappeared in March in the last two years (2017–2018). However, sea ice thickness and snow depth in September increased with the positive anomaly in the southwestern Arctic Ocean.