西太平洋副高脊线北抬至25°N的OLR特征及诊断分析

取西太平洋副热带高压脊线北抬至 2 5°N日期和射出长波辐射 (OLR)月平均资料为素材 ,确定副高脊线北抬至 2 5°N指数和异常年例 ,揭示异常年例的OLR特征 ,进行诊断判据分析 ;主要结果有 :(1 ) 6月东亚中低纬地区的OLR距平场由中纬向低纬若呈偏低 (高 )、偏高 (低 )、偏低 (高 )分布时 ,副高脊线北抬至 2 5°N易于偏早 (迟 ) ;(2 )在分析诊断判据时 ,上一年 1 1月侧重南半球澳大利亚地区OLR所显示的信息 ;而当年三月侧重西太平洋辐合区OLR所显示的信息。

Diagnosis of OLR Features of West Pacific Ocean Subtropical High Ridge Carried to 25°N

Based on the date of the West Pacific Ocean subtropical high ridge carried to 25° N and monthly mean OLR data, the index of the subtropical high ridge and anomalous years are defined. And OLR features of the anomalous years are revealed. The results are as follows: (1) when OLR anomaly arranges in low( high ), high( low ), low( high ) on June in East Asia from middle latitude to low latitude,it is easy that subtropical high ridge carried to 25°N early( late ) than normal. (2) when diagnosis and analysis are being made, particular attention should be paid both to the last November information of Australia in Southern Hemisphere and to the current March information of convergence region over West Pacific Ocean.