INTERANNUAL VARIABILITY OF HEAT CONTENT, AND ITS RELATIONSHIP WITH THE SUMMER MONSOON INTENSITY, IN THE SOUTH CHINA SEA

Abstract:

This study analyzes the Ishii 700 m heat content (HC) in the South China Sea (SCS). During the 1978–C2012 period, the HC in the SCS changed dramatically on interannual timescales. Three main findings emerged from the analysis. 1) The first spatial pattern of the empirical orthogonal function (EOF1) was consistently distributed over most of the SCS, whereas that of the second empirical orthogonal function (EOF2) showed a dipole signal. 2) The HC anomalies in the SCS were closely related to the SCS summer monsoon intensity. When the HC over most of the SCS increased (decreased) in previous winter, the SCS summer monsoon was strengthened (weakened). Therefore, the HC behavior in the SCS during previous winter can well predict the intensity of the SCS summer monsoon. 3) HC anomalies in the SCS largely influence the monsoon and Walker circulations, in turn affecting the western Pacific subtropical high and finally the SCS summer monsoon.