Interannual relationship between the Asian-Pacific Oscillation and summer sea surface temperature in the North Atlantic

Abstract

Over the last two decades, there has been increasing interest in investigating the connection between the Asian-Pacific Oscillation (APO) and weather and climate on regional and global scales, but the impacts of the APO on sea surface temperature (SST) remains unclear. Using the multisource reanalysis dataset and observed SST data, we evaluated the interannual relationship between the APO and SST in the North Atlantic (NASST) during the period 1979-2016. The results show that there exists a statistically significant positive interannual relationship between APO and NASST and this connection can be attributed to the Rossby wave train that originates in Asia and propagates to Europe, which is triggered by the APO forcing. Further examination revealed that the cloud radiation, air-sea heat exchange and oceanic dynamic process induced by APO are crucial in modulating the interannual variability of the NASST. Additionally, the numerical simulation results from the linear baroclinic model also provide additional evidence for this linkage.