利用TBB资料对西太平洋副热带高压特征的分析和描述

Analysis and Description of West Pacific Subtropical High Using TBB Data

利用卫星TBB资料和500 hPa位势高度场资料, 分析了西太平洋副热带高压(下称西太副高)的北进及南撤特征。结果表明: 西太平洋副热带地区的TBB场呈带状分布, >275K的TBB区随季节的变化从1月至12月表现为先北跳又南落之势, 它与西太副高的北跳和南落同步, 其大值区可以表征西太副高的范围。西太副高脊线(500 hPa上的u=0 线)与TBB大值区轴线的走向基本一致。不同季节可以不同的TBB值来描述西太副高。同时指出, 以TBB大值区所描述的西太副高与雨区的配置较588 gpdm等高线与雨区的配置要好, 并且可以避免588 gpdm等高线所产生的假象。另外, 每3 h TBB场的分析可为暴雨的逐3 h预报提供参考。

The distribution and evolution of TBBand the %u%=0 contour at 500 hPa in West Pacific Subtropical Region(WPSR) is analyzed in this paper. The results showed that the belt of TBB≥275K in the WPSR, which corresponds with that of West Pacific Subtropical High(WPSH), shifts northward first and southward later with the season’s change, therefore the region of TBB≥275K can be used to describe the zoneof WPSH and the corresponding TBB’s scale described by WPSH changes with seasons; the ridge line of WPSH (the %u%=0 contour at the level 500 hPa) also agrees with the axis of the zone of TBB≥275K. Meanwhile, it can be revealed that WPSH described by TBBmatches better to the heavy rain region than 588 gpdm contour, avoiding from the false defect in drawing WPSH by 588 gpdm contour. Moreover, TBBdata set of every 3 h is beneficial to the heavy rain forecast.