新乡市近60年降水序列变化规律及干旱预测

Precipitation change in recent 60 years and drought prediction in Xinxiang

新乡市属严重缺水地域,近年来干旱的加剧使水资源短缺问题更加突出,严重制约了区域社会经济的发展。因此,对该地区进行降水序列的分析以及干旱的预测显得尤为重要。利用新乡市1953—2010年的年降水量资料,采用一元线性回归法和Mann—Kendall法分析新乡市降水的时间变化规律,结果表明:该地区近60年来年降水量呈减少的趋势,干旱发生频率有增加的趋势。以1953—2000年的年降水量资料为建模数据,2001—2010年的年降水量资料为检验数据,运用灰色系统的灰色预测方法,建立新乡市的灰色预测GM(1,1)模型,对该地区未来一定时期内干旱发生的时间进行预测,经检验该预测模型精度高,检验结果与实际相符,故可用该模型对新乡市未来的干旱年进行预测。预测结果显示,新乡市将在2012—2013、2020—2021、2028—2029年期间发生干旱。

Xinxiang City in He’nan Province is a region with a serious water shortage .Recently ,the problem of water shortage has become even more outstanding due to the aggravation of drought ,which has seriously restricted the so-cial and economic development .Thus it is important to analyze the trend of precipitation change and to conduct drought forecasting in this region .Based on the annual precipitation in Xinxiang during 1953 to 2010 ,the temporal variation of precipitation was analyzed by using linear regression equation and Mann-Kendall method .The results showed that the precipitation tended to decrease and the drought frequency tended to increase in Xinxiang in current 60 years .With the observed values of annual precipitation during 1953 to 2000 as modeling data and those during 2001 to 2010 as testing data ,and by using gray system technique ,the gray prediction model GM （1 ,1 ） of Xinxiang was established ,the time of drought occurrence in the future was forecasted .The testing results showed a good precision and were consistent well to the actuality .Therefore ,this model could be used to predict the years of drought .It was indicated that the drought would take place in the period of 2012-2013 ,2020-2021 and 2028-2029 .