宁夏春季首场透雨的气候预测探索

利用目前在统计预报中广泛应用的最优子集回归预报法,作宁夏南部山区及银川地区春季首场透雨出现日期的统计预报,给出了具体的预报方程和拟合效果分析。并对近30 a来宁夏南部山区及银川地区首场透雨出现日期的变化特征进行了较详细的分析。研究结果表明:银川地区3月份出现首场透雨的气候概率为23.3%、4月份为20%、5月份为23.3%、6月份为33.3%,出现机会相对较多。30 a来春季首场透雨出现日期:20世纪70年代相对较晚,80年代偏早,90年代介于70、80年代之间。南部山区春季首场透雨出现时间相对比较集中,其中4月份出现的气候概率为53%,其次是5月份和3月份,分别为20%和17%,最小的是6月份,只占10%,从近30 a来的总趋势看,南部山区春季首场透雨出现日期在波动中略有推迟现象。利用最优子集回归预报法对宁夏春季首场透雨出现日期的预测具有理想的拟合效果。

Climate Prediction Research on the First Soaking Rainfall in Ningxia

The dates of the first soaking rainfalls in the south and middle parts of Ningxia were forecasted statistically by using the optimal subset regression method,the forecast equation was set up and its effect was analyzed,and the change of the dates of the first soaking rainfall in the regions in recent 30 years was discussed in detail.Results show that the occurrence probability of the first soaking rainfall is 23.3% in March,20% in April,23.3% in May,and 33.3% in June in Yinchuan region,during the last 30 years the dates of the first soaking rainfalls were later in 1970s,earlier in 1980s,and medium in 1990s between that in 1970s and 1980s.The dates of the first soaking rainfall concentrated relatively in southern mountain areas of Ningxia,the probability of occurrence is 53% in April,20% and 17% in May and March,and only 10% in June,and it is found that there is a slight trend of postponing with fluctuation for the dates of the first soaking rainfalls in this region in recent 30 years.The effect of forecast using the optimal subset regression method for the date of the first soaking rainfall is good in Ningxia.