Research on the Anomalies of Atmospheric Circulation of the Extremely Severe Drought in Southwest China
The 1992 drought,the 2006 drought and the 2009-2010 drought were identified as the extremely severe drought according to the precipitation index.Based on the NCEP/NCAR reanalysis data and the daily precipitation data of the 143 stations in Southwest China from 1961 to 2010,the temporal distributive features of the extremely severe drought and the anomalous atmospheric circulation in drought period are analyzed.Results show that the rainless period starts from June and ends in September.In the drought period,the evolution of height field and normalized field has regional characteristics:southwest China is controlled by high pressure system with higher geo-potential height.Moreover,the water vapor transport from the bay of Bengal and South China Sea was reduced under the control of abnormal northeast moisture,which resulted in the persistence of the extraordinary drought.
Southwest Chinadroughtprecipitationheight fieldwater vapor field
NETL
NSTL
万方数据
维普
