Teleconnection between Winter Arctic Oscillation and Southeast Asian Summer Monsoon in the Pre-Industry Simulation of a Coupled Climate Model

Abstract

A 600-year pre-industrial simulation with Bergen Climate Model (BCM) Version 2 is used to investigate the linkage between winter Arctic Oscillation (AO) and the Southeast Asian summer monsoon (SEASM) on the inter-decadal timescale. The results indicate an in-phase relationship between the AO and SEASM with periods of approximately 16-32 and 60-80 years. During the positive phase of winter AO, an anomalous surface anti-cyclonic atmosphere circulation appears over North Pacific in winter. The corresponding anomalies in ocean circulation and surface heat flux, particularly the latent and sensible heat flux, resemble a negative Pacific Decadal Oscillation (PDO)-like sea surface temperature (SST) pattern. The AO-associated PDO-like winter SST can persist into summer and can therefore lead to inter- decadal variability of summer monsoon rainfall in East and Southeast Asia.

Keywords:

• Southeast Asian summer monsoon
• Arctic Oscillation
• Pacific Decadal Oscillation
• inter-decadal timescale
• sea surface temperature