Influence of South China Sea SST and the ENSO on Winter Rainfall over South China |
| |
Authors: | ZHOU Lian-Tong Chi-Yung TAM ZHOU Wen and Johnny C L CHAN |
| |
Institution: | Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100190, CityU-IAP Laboratory for Atmospheric Sciences, City University of Hong Kong, Hong Kong,CityU-IAP Laboratory for Atmospheric Sciences, City University of Hong Kong, Hong Kong, Guy Carpenter Asia-Pacific Climate Impact Centre, School of Energy and Environment, City University of Hong Kong, Hong Kong,CityU-IAP Laboratory for Atmospheric Sciences, City University of Hong Kong, Hong Kong, Guy Carpenter Asia-Pacific Climate Impact Centre, School of Energy and Environment, City University of Hong Kong, Hong Kong,CityU-IAP Laboratory for Atmospheric Sciences, City University of Hong Kong, Hong Kong, Guy Carpenter Asia-Pacific Climate Impact Centre, School of Energy and Environment, City University of Hong Kong, Hong Kong |
| |
Abstract: | 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 significant correlation with Nino-3 and
SCS SST. Analyses show that in El Nino 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
Nino-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. |
| |
Keywords: | ENSO South China Sea SST rainfall convective instability potential vorticity |
本文献已被 万方数据 SpringerLink 等数据库收录! |
| 点击此处可从《大气科学进展》浏览原始摘要信息 |
| 点击此处可从《大气科学进展》下载免费的PDF全文 |
|