盛夏农业干旱事件的分析与预报

Analysis and Forecast of Agricultural Drought Event in Midsummer

根据农作物生长规律,与农业部门一起共同制定了当地盛夏农业干旱事件的标准,并从气象学角度对其分布规律及特性进行分析,得出造成盛夏农业干旱事件的主要有三种重要的天气类型(纬向环流型、大陆高压控制型、副高西进控制型)。通过对西北太平洋地区海水表层月平均海温、北半球极涡的年平均强度、冬季气温与历年(1964-2003年)干旱事件发生频率进行分析,采用最优子集回归法建立了干旱事件预测方程,进一步提高了干旱事件的预测能力,2004年和2005年预测结果与实况相符。

Accorded to the crop growth rules, we formulated the standard of the drought event with agricultural department together and analyzed the drought distribution from the aspect of meteorology. It was concluded that there were three kinds of important weather types led to the drought event, e. g. latitude circulation, continent high pressure control and subtropical high west enter control type. Based on the analysis of the relation of drought event occurrences from 1964 to ：2003 with the monthly average temperature of sea surface in the Northwest Pacific Region, the annual mean vortex intensity in the Northern Hemisphere and the temperature change in winter, the forecast equation of the drought event was established by using the optimized subset regression method. The forecast results were validated for ：2004 and ：2005 with highly coherence.