20世纪西北地区降水量变化特征

Changing Features of Precipitation over Nothwest China During the 20th Century

利用英国东安哥拉大学气候研究中心 (CRU)的Hulme最新的 190 0 - 1998年的全球降水量资料 ,分析了 2 0世纪西北地区降水量的变化特征 .结果表明 ,2 0世纪西北地区降水量处于下降通道中 ,后期略有回升 ;西北地区东部和西部降水量的年代际变化有相反的趋势 ;2 0世纪后期西北地区中西部降水量有明显的增多趋势 ,东部降水量持续偏少 ,干旱连年发生 .

The precipitation dataset for global land from 1900 to 1998 presented by Dr. Mike Hulme (Climate Research Unit, East Angles University, UK) is the longest global precipitation dataset available now. The evolutional trends of precipitation were studied by using the long historical data in the 20 th century in Northwest China. It is found that the mean precipitation appeared a downward trend from the beginning of the 20 th Century, but a slight upward trend appeared in the end of the 20 th Century. The interannual trends of precipitation between the East and the West showed a contrary variation. In the end of the 20 th century, the mean precipitation appeared an obviously upward trend in the central and western portions of Northwest China, but in the east the mean precipitation continuously decreased, many drought events have happened.