相似离度在钦州市月降水量预报中的应用

Application of Similitude Degree of Separation to the Monthly Precipitation Forecast in QIN Zhou

试用钦州市 4月份降水量与前期 5 0 0 HPA各月平均高度场作相关分析 ,选择一批优势相关区 ,并用历年各优势相关区内相关系数 r绝对值大于等于 0 .4 ,且点数为 3点以上并连在一起的所有格点的平均值与预报年的相应区域内格点平均值作相相似离度计算 ,预报 4月雨量。并将 1996～ 2 0 0 1年作为试报年 ,结果 6年报对 5年 ,准确率为 83%。

A correlative analysis is made between the precipitation of Qinzhou in April and the average height field of early 500HPA in each month. Based on this, a lot of advantageous correlative zones are selected together with the computation by way of similitude degree of separation, using the average values of all the connected grid points of at least 3 points in each advantageous correlative zone in the past years, whose absolute correlation coefficient r is bigger or equals to 0.4, and the average values of grid points in the corresponding zones of the forecast year, to forecast the precipitation in April of the year. The test is done during 1996 2001, and the forecasts of 5 years among this period are accurate, with an accuracy rate of 83%.