Influence of Winter Tasman Sea SST on the Antarctic Peninsula: A Perspective from Historical Simulations

The winter temperature variability of the Antarctic Peninsula (AP) has been proven to be influenced by sea surface temperature (SST) anomalies over the Tasman Sea. Using outputs over an extended time period from historical experiments, the skills of CMIP6 models in simulating the atmospheric responses to Tasman Sea SST are evaluated in this study, with an emphasis on the relationships with AP temperatures. The spatial correlation coefficient and normalized standard deviation are used as the evaluation metrics. Corresponding results suggest that the majority of CMIP6 models can capture the basic spatial distributions of Tasman Sea-related teleconnections across the Southern Hemisphere extratropical region, featuring a Pacific–South America-like pattern. However, the overestimation of atmospheric interannual variability and the underestimation of oceanic interannual variability in CMIP6 models result in a considerable amplification of the atmospheric responses to SST anomalies. The model uncertainty in depicting the relationships between Tasman Sea SSTs and AP surface temperatures, as well as the associated teleconnections, can partially be attributed to variations in grid resolutions among models. Additionally, further analysis of the Antarctic sea ice shows that the Tasman Sea SST may contribute to the interannual variability of the Antarctic dipole in CMIP6.