大气科学进展(英文版)
大氣科學進展(英文版)
대기과학진전(영문판)
ADVANCES IN ATMOSPHERIC SCIENCES
2010年
4期
832-844
,共13页
周连童%Chi-Yung TAM%周文%Johnny C. L. CHAN
週連童%Chi-Yung TAM%週文%Johnny C. L. CHAN
주련동%Chi-Yung TAM%주문%Johnny C. L. CHAN
ENSO事件%南中国海%冬季降水%SST%冬小麦%Sea%中国南部%降雨影响
ENSO事件%南中國海%鼕季降水%SST%鼕小麥%Sea%中國南部%降雨影響
ENSO사건%남중국해%동계강수%SST%동소맥%Sea%중국남부%강우영향
ENSO%South China Sea%SST%rainfall%convective instability%potential vorticity
The present study investigates the influence of South China Sea (SCS) SST and ENSO on winter (January-February-March; JFM) rainfall over South China and its dynamic processes by using station observations for the period 1951-2003, Met Office Hadley Center SST data for the period 1900-2008, and ERA-40 reanalysis data for the period 1958-2002. It is found that JFM rainfall over South China has a sig- nificant correlation with Nio-3 and SCS SST. Analyses show that in El Nio or positive SCS SST anomaly years, southwesterly anomalies at 700 hPa dominate over the South China Sea, which in turn transports more moisture into South China and favors increased rainfall. A partial regression analysis indicates that the independent ENSO influence on winter rainfall occurs mainly over South China, whereas SCS SST has a larger independent influence on winter rainfall in northern part of South China. The temperature over South China shows an obvious decrease at 300 hPa and an increase near the surface, with the former induced by Nio-3 and the latter SCS SST anomalies. This enhances the convective instability and weakens the potential vorticity (PV), which explains the strengthening of ascending motion and the increase of JFM rainfall over South China.