open access

https://hdl.handle.net/2115/53185

Influence of sea surface temperature on the intraseasonal variability of the South China Sea summer monsoon

英語

Intraseasonal variablity

2012-09

Springer-Verlag

Climate Dynamics

39(5)

1209-1218

The objective of this study is to examine, based on recently available high resolution satellite and observational data, the evolution and role of sea surface temperature (SST) in influencing the intraseasonal variability of the South China Sea (SCS) summer monsoon (SM). The study focuses on the 30-60 day timescale when the northward propagating anomalies are dominant over the SCS. Composite analysis of the SST maximum events during SCS SM shows that increased SST anomalies over the SCS are significantly influenced by the downward shortwave radiation flux anomalies, with the suppressed surface latent heat flux anomalies supplementing to it. A thermal damping of the positive SST anomalies induces positive upward heat fluxes, which then destabilize the lower atmosphere between 1000 hPa and 700 hPa. The positive SST anomalies lead the positive precipitation anomalies over the SCS by 10 days, with a significant correlation (r = 0.44) between the SST-precipitation anomalies. The new findings here indicate an ocean-to-atmosphere effect over the SCS, where underlying SST anomalies tend to form a favorable condition for convective activity and sustain enhanced precipitation during the SCS SM. It is also argued, based on our observations, that the negative sea level pressure anomalies induced by the positive SST anomalies play a role in enhancing the northward propagation of the intraseasonal anomalies over the SCS.

学術雑誌論文

Accepted Manuscript

The original publication is available at www.springerlink.com

0930-7575