Changes in Precipitation Extremes in Lancang River Basin, 1960-2005
Extreme precipitation is an important aspect of climate change. According to the estimation using the latest climate models, the extreme precipitation events will become frequent in a warming world. Significant increases of the very heavy precipitation and decreases of light and moderate precipitations have indeed been observed over most land areas of the globe in the last few decades. The Lancang River, with a relative altitude difference of about 5000 m, flows through 13 latitudes and 6 climatic zones. It is rarely seen in the world and has important scientific values for climatology, hydrology, geography and ecology. Since 1960, the basin has experienced a significant increase in temperature like most parts of the world. Studying the changes of extreme precipitation events in the basin in the context of global wanning is of great importance.Based on a daily precipitation dataset of 35 meteorological observation stations distributed in and around the Lancang River basin, trends of precipitation amounts, precipitation days and daily precipitation intensity during a 45-year period (1961-2005) of 4 different classes ranging from less than 5, 5-10, 10-50 and larger than 50 mm were analyzed, and the precipitation frequency and the proportion of precipitation amount of each precipitation class were calculated. The result showed that all the indexes varied spatially, and for the basin as a whole,the frequency of the extreme events increased obviously. Analysis of a typical station indicated that the increase of extreme precipitation and the randomness of the climatic system might be closely related with each other.
NETL
NSTL
万方数据
维普
