1998年夏季西太副高活动与凝结潜热加热的关系

利用1998年南海季风试验逐日再分析资料,分析了1998年夏季梅雨期内凝结潜热加热对西太平洋副热带高压(下称西太副高)中短期活动的影响。结果表明,不同位置的凝结潜热加热对西太副高的作用是不同的:当西太副高西侧的降水在它的边缘发生时,释放的凝结潜热加热可能迫使西太副高东退,离它较远处的降水则可能诱使西太副高西伸;西太副高北侧降水释放的凝结潜热加热将阻止它北进;南侧降水则有推动西太副高北进的作用。当南北两侧的凝结潜热加热等强度时,它原地不动,但强度增强,达到一定强度时西伸;若某一侧加热强度减弱,西太副高则有向该侧移动的趋势。

Relationship between Activity of West Pacific Subtropical High and Condensation Latent Heating in Summer of 1998

By means of daily reanalysis data of the South China Sea Monsoon Experiment in 1998,the influence of condensation latent heating on mid- and short-term activities of West Pacific Subtropical High(WPSH) during Meiyu period 1998 is studied.Results show that the location of condensation latent heating has some impact on WSPH.The condensation latent heating released by rainfall on the west side of WSPH may force an eastward withdrawal of WPSH,while the rainfall is to far west of WPSH will lead to a westward extension of WPSH.The latent heating to the north of WPSH prevents the WSPH from moving northward and vice versa for that to the south of WPSH.When the heating to both the south and north of WPSH has the equal intensity,the WPSH is immovable,but it will intensity and extendes westward when it is strong enough.If the intensity of heating on one side weakens,WPSH moves toward that side.