Abstract:

Using the monthly Outgoing Longwave Radiation (OLR) data provided by NOAA during the period 1979~2008,the convection around the Philippine was analyzed and two indexes named Philippine Convection Index (PHCI) and Philippine Convection Position (PHCP) were defined.Based on the PHCI and PHCP,the relationship of the PHCI/PHCP and the summer precipitation in the Yangtze River Basin were studied.The results show that the different grades of the PHCI have different effect on the rainfall of the Yangtze River Basin.When the PHCI is the highest,the precipitation of the Yangtze River Basin is much more,but when the index is the lowest,the precipitation is less in the middle reaches of the Yangtze River and the Jianghuai Valley.When the PHCI is higher,the precipitation is more in the north of the middle reaches of the Yangtze River,but when the index is lower,the precipitation is much less in the Yangtze River Basin.When the PHCI is slightly high,it makes the more precipitation in the lower reaches of the Yangtze River,and when the index is slightly low,there makes no strong effect.The precipitation is less in the lower reaches of the Yangtze River when the PHCP is in the north and east,while in the other three directions (the north and west,the south and east,the south and west) the precipitation is more in the middle reaches of the Yangtze River.At the same time,when the PHCP is in the south and east,the precipitation is more in the lower reaches of the Yangtze River.When the PHCP is in the south,the PHCI is higher.But it is not the same variation when the PHCP is in the north.Furthermore,when the longitude position is in the west,the PHCI is higher, and vice versa.〖