中层涡旋诱生南海热带低压形成的位涡反演分析  

PV Inversion Analysis of a Mid-level Vortex Induced a Tropical Depression Formation in South China Sea

作　　者：袁金南[1] 谷德军[1] 廖菲[1] 

机构地区：[1]中国气象局广州热带海洋气象研究所,广州510080

出　　处：《高原气象》2015年第1期93-102,共10页Plateau Meteorology

基　　金：国家重点基础研究发展计划(973计划)项目(2009CB421500);气象行业专项(GYHY201106036);国家自然科学基金项目(40875026;91015011);广东省自然科学基金团队项目(8351030101000002)

摘　　要：利用NCEP 1°×1°最终分析资料FNL和位涡反演方法,对2006年8月下旬一次中层涡旋诱发南海热带低压的形成过程进行了分析。结果表明,在中层涡旋诱发南海热带低压形成时高层暖心结构经历了由上向下逐渐发展的过程,而中层气旋性环流经历了由上向下快速发展的过程。高层暖心结构的向下发展主要与中低层凝结潜热加热作用和干空气从高层侵入有关,而高层波动的影响不明显,暖心发展到达近海面需要有底层热力异常和中低层凝结潜热加热作用的共同配合。中层气旋性环流的向下发展主要与中低层凝结潜热加热作用有关,高层波动对中低层涡度的影响不明显,而底层热力异常主要在900 h Pa以下产生负涡度。综合分析表明,中低层凝结潜热加热对南海热带低压的生成和发展起关键作用。Using NCEP 1° × 1° Final Analysis( FNL) data and potential vorticity( PV) inversion technique,the process of a mid-level vortex induced tropical depression formation in the South China Sea( SCS) in late August2006 w as analyzed. The results show that: The upper w arm-core structure experienced a process of gradual development from up to dow n and the mid-level cyclonic circulation experienced a process of fast development from up to dow n during the mid-level vortex induced tropical depression formation in the SCS. The dow nw ard development of upper w arm-core structure is mainly associated with the action of condensation latent heating in middle and low level and dry air intrusion from high level to middle level. The influence of high level fluctuations is not obvious. How ever,the w arm-core developing dow nw ard to near sea surface need the common actions of bottom thermodynamic anomaly together with condensation latent heating in middle and low level. The dow nw ard development of mid-level cyclonic circulation is also mainly associated with the action of condensation latent heating in middle and low level. The influence of high level fluctuations on the vorticity in middle and low level is not obvious. And the bottom thermodynamic anomaly mainly causes negative vorticity below 900 h Pa. The comprehensive analysis show s that the condensation latent heating in middle and low level plays a key role in the tropical depression formation and development in the SCS.

关 键 词：中层涡旋 南海热带低压 位涡反演 热力和动力结构 

分 类 号：P458.2[天文地球—大气科学及气象学]