一种改进的判别方法及其在纵向岭谷夏季降水预测中应用  

An improved discriminant method and its application in forecasting summer precipitation in Longitudinal Range-Gorge Region

作　　者：尤亚磊[1] 钟爱华[1] 张利娜[1] 

机构地区：[1]云南大学大气科学系,云南昆明650091

出　　处：《云南大学学报（自然科学版）》2005年第4期343-347,共5页Journal of Yunnan University(Natural Sciences Edition)

基　　金：国家重点基础研究发展计划资助项目(2003CB415100).

摘　　要：在遵循Fisher判别准则的基础上,提出了一种判别系数和判别临界值随时间变化的新方法,并应用于能反映纵向岭谷区域降水主要变化规律的镇沅测站7月份降雨量的预报中.在前人工作指出印度洋海温变化对该区降水变化有显著影响的基础上,以前期秋季、冬季和春季印度洋海温距平的纬向梯度为预报因子,建立判别预报方程.实际应用结果表明,此方法具有较好的历史回报率和外推预报率;同时具有良好的预报稳定性.<Abstrcat>According to Fisher discriminant criterion,a new method whose discriminant coefficient and critical value change along with time was put forward and applied to forecast precipitation in July of the Zhengyuan observational station whose rainfall can mostly reflect the changing rule in Longitudinal Range-Gorge Region.Based on the former researches that pointed out Indian Ocean temperature distinctly influenced on the precipitation change over the region,a discriminant predictive equations were built with the former autumn,winter and spring zonal gradient of sea surface temperature anomalous.The application results indicated that the new method had efficient fitting and forecasting accuracy as well as better forecasting stability.

关 键 词：FISHER判别准则 时变参数 夏季降雨 纵向岭谷 

分 类 号：P456[天文地球—大气科学及气象学]