Relationship Between Snow Anomaly in East of Qinghai-Tibet Plateau and Spring Rainfall in Southwest China
Based on the data set of snow in east of Qinghai-Tibet Plateau and spring rainfall in Southwest China from 1961/1962 to 201 1/2012,the relationship and its temporal variations between snow anomaly in prophase and spring rainfall in Southwest China were analyzed by using methods such as SVD,linear regression analysis,sliding correlation analysis,etc.The results indicate that snow in December and January in east of Qinghai-Tibet Plateau had a good indicative significance to spring rainfall in the Southwest region of Southwest China,and the key region of snow effect located at the southeast of Southern Qinghai Plateau,the north of western Sichuan Plateau and eastern Tibet gorge,with Banma,Shiqu and Dingqing as center,respectively.The main response of spring rainfall was positive,the remarkable regions covered almost the whole Southwest of Southwest China except the northwest and Southwest of Yunnan, especially the juncture region of Sichuan and Yunnan,with Huili and Huaping as center.By using sliding correlation analysis,it was found that the relationship between the prophase snow anomaly in the key area and spring rainfall in the Southwest region of Southwest China always kept positive correlation and its interdecadel change was significant.The period from 1961 to 2011 could be separated into three stages.The first stage from 1961 to 1984 was below 95% confidence level,the second stage from 1985 to 1995 was above 99%confidence level,and the third stage from 1996 to 201 1 was between 95%and 99%confidence level.There happened an obvious shift when one stage changed to the next.The interdecadal variation characteristics of the correlationship were close agreement with winter snow in east of Qinghai -Tibet Plateau.In recent years,the correlationship showed the slight decline compared with the previous stage,but still stablely remained above 95%confidence level and could be taken as an important reference for spring rainfall prediction in the Southwest region of Southwest China.
NETL
NSTL
万方数据
维普
