百年来中国黄河流域区域性旱涝气候突变

ABRUPT CLIMATIC CHANGE OF DROUGHT AND FLOOD IN THE HUANGHE RIVER BASIN DURING THE LAST 100 YEARS

通过对近百年来黄河流域各区域旱涝气候突变特征的研究,表明该流域的大部分地区旱涝气候变化在本世纪10年代内出现突变现象,而且是从一个相对的偏涝期进入偏早期的转变。并且初步分析了黄河流域出现旱涝气候突变的可能成因。

In this paper,the drought/flood indexes for the divisions in the Huanghe River Basin during the last 100 years (1891—1990) are analysed to reveal abrupt climatic change using the Mann-Kendall Test.It is found that there existed abrupt climatic change of drought/flood in 1910 and 1912 over the middle and lower reaches respective- ly,but no such obvious abrupt climatic change is found over the upper reaches.These facts show that there existed abrupt climatic changes of drought/flood for most parts of the basin during the 1910s,which were jumps from flood to drought phases.Meanwhile, it is should be pointed out that the jump was not non-local event in the basin.In addi- tion,the possible reasons causing the jumps are discussed.By analysing the South Oscil- lation Index and the air temperature of the Northern Hemisphere using the same test, one can see that their abrupt changes occurred earlier than that of the drought/flood,in- dicating that these may be improtant background conditions for the event of abrupt cli- matic change of drought/flood.