贺州市春季降水旱涝分析及灾变预测

利用贺州市四站1965~2004年春季降水资料,运用z指数和区域旱涝指数对贺州地区春季旱涝情况进行计算分类,并对重旱涝典型年份500hPa环流特征量和4月平均环流场展开分析,发现:贺州地区春季极易发生局部旱涝灾情,90年代以来重旱涝年份出现频率明显增大;在重旱年副高强度强,西伸脊点明显偏西,南支槽偏西偏弱,极涡中心偏东,亚洲中高纬高度偏低,在重涝年则相反。同时,通过建立GM(1,1)灾变预报模型,以重旱涝年份出现顺序为原始序列作模拟预报,其结果具有较好的应用价值。

The Spring Flood And Drought Analysis And The Disaster Forecast In He Zhou

This paper conducts the computation classification for the spring flood and drought situation in He Zhou by using the spring precipitation data in four weather stations of He Zhou during 1965-2004,and the z index,and the index of regional flood and drought.And analyzes the 500hPa circulation characteristic of severe drought of typical years and the average circulation field in April and finds that local flood and drought are easily occurred in spring in He Zhou,the frequency of the disasters increases obviously since the 90's.Subtropical high is intensive,its crest point is obviously to the west,the southern trough is weak and to the west,the center of the polar vortex is to the east,the latitude in Asia is highly somewhat low,however it is opposite in the severe flood years.Meanwhile,the paper uses the year order of severe flood and drought as the primitive sequence to make the simulation forecast through establishing GM(1,1) disaster forecast model,its result shows quite good application value.