祁连山东部局地防雹效果分析

The Effects of Artificial Prevention of Hails on Local Districts in the Eastern Part of the Qilian Mountain

利用甘肃省祁连山东部天祝县乌鞘岭气象站1951年-2004年54a年冰雹日资料和天祝县1961年-2004年44a粮食产量资料，经相关系数分析法、序列试验法和WOLCH检验法，分析了冰雹及粮食产量的关系和防雹前后粮食产量的变化．发现年冰雹日数与年粮食产量呈负相关，相关系数为-0．48，达到了0．01以上显著水平．实施高炮和火箭防雹作业后，年粮食产量增加492．9kg／hm^2，相对增加率22．5％，检验效果达到了0．01以上显著水平，可信度达99％以上．

By means of the eorrelativity analysis method and list test method and WOLCH checkout method, the relation between annual hail days and annual foodstuff output was discussed; the changes in foodstuff outputs before and after the prevention of hails were analyzed by using the annual data of Wushaoling weather station from 1951 to 2004 and annual foodstuff output data from 1961 to 2004 in Tianzhu county which is located in the eastern part of the Qilian mountains. It showed that annual hail days and annual foodstuff output were inversely correlated; the coefficient of correlativity was -0.48, which was remarkably higher than 0. 05. After preventing hail disasters with anti-aircraft cannons and rockets, the annual foodstuff output was increased to 492. 9 kg/hm^2; the relative increasing rate was 22. 5%. Checkout effect went higher than 0. 01, and the reliability of this measurt reached beyond 99%.