福建前汛期降水趋势的OLR特征及诊断分析

本文取全省25个代表站5－6月的降水资料和射出长波辐射（OLR）月平均资料为素材，首先确定降水偏差指数（即相对距平）和异常年例，其次揭示异常年例和基本规律的OLR特征，最后进行诊断判据分析及对2001－2002年福建前汛期水趋势诊断；主要结果有：（1）东亚中低纬地区的OLR由中纬向低伟若呈高（低）、低（高）、高（低）分布时（流场呈辐散（辐合）、辐合（辐散）、辐散（辐合）分布），福建前汛期降水易于偏多（少）；（2）在诊断判据分析时上一年十月侧重南半球所显示的信息；而当年一月侧重西太平洋辐合、巴基斯坦－印度北部－青藏高原西部和东南亚地区所显示的信息；（3）OLR距平分布图所提供的信息在实际诊断过程中具有应用价值。

THE ANALYSIS BY DIAGNOSIS AND OLR FEATURE OF RAINY TREND WITHIN FORWARD FLOODTIME IN FUJIAN PROVINCE

The precipitation data during May-June at 25 representative meteorological stations in Fujian province and monthly mean of OLR data were selected as material. First,the rainy trend index and anomalous years were defined. Next,OLR feature of basic regularity and anomalous year were revealed. Finally, diagnosis analysis and rainy trend diagnosis within forward floodtime during 2001-2002 in Fujian province were completed. We have come to the following conclusions:1) when OLR on middle-low latitude area in East Asia from middle latitude to low latitude showed high(low),low(high),high(low)distribution the stream field showed divergence (convergence),convergence (divergence),divergence (convergence), the precipitation probably can be more (less) than normal during forward floodtime in Fujian. 2)Diagnosis and analysis of the rain in Southern hemisphere are mainly based on the information of last October last , but the convergence region in West Pacific Ocean,Pakistan,Orth India,West Tibetan Plateau and Southeast Asia plays more important role in the information of January in this year. 3) It is helpful to apply the information provided by the distributing chart of OLR anomaly in the course of practical diagnosis.