气象学报2011，Vol.69Issue(3)：464-471,8.
南亚高压对亚洲季风区夏季对流层上层水汽异常分布的动力效应
A study of the dynamic effect of the South Asian high on the upper troposphere water vapor abnormal distribution over the Asian monsoon region in boreal summer
摘要
Abstract
Proper recognition of the water vapor distribution and formation mechanism in the upper troposphere (UT) over the Asian monsoon region is of great significance for understanding of global climate change. Based on the latest Earth Observing System Microwave Limb Sounder (EOS-MLS) satellite retrievals product, the study firstly presented a qualitative analysis of the anomaly characteristics of the upper troposphere water vapor distribution. Then we studied the air particles horizontal transport characters in the upper troposphere layer over the Tibetan Plateau and its adjoint areas using the National Centers for Environmental Prediction (NCEP) reanalysis data of 2005 and a particle dispersion model FLEXPART. Also the dynamical effects of the south Asian high, which are able to trap the constituents in its core, in determining and maintaining the water vapor distribution are investigated quantitatively.The analysis of the EOS-MLS satellite retrieval products shows that the Asian monsoon region is an area of particular interest, as it is characterized by a persistent maximum of water vapor in the upper troposphere. The location of maximum water vapor on 215 hPa coincides with the deep convection. However, the water vapor maximum at 147 hPa does not spatially correspond to the maximum of convective activity, but is located inside the South Asian high. The distribution of carbon monoxide over this area shows the same characteristic as the water vapor. This result suggests an important role of the South Asian high in determining and maintaining the water vapor distribution. For every numerical simulation, 10000 forward parcels trajectories were calculated for the summer of 2005. The result of idealized ensemble numerical simulations (total 66 groups) indicates that the South Asian high circulation acts as a horizontal transport barrier in the upper troposphere and low stratosphere during the boreal summer. The effects of the South Asian high are mostly in the height between 12 km and 15 km vertically. While in horizontal direction, the close circumfluence of the South Asian high enables air particles to stay inside the anticyclone for more than one month. This might be one of the explanations of the zonal anomaly distribution characteristics of vapor over the Asian summer monsoon region.关键词
南亚高压/对流层上层/水汽异常分布/动力效应Key words
South Asian high/Upper troposphere/Vapor anomaly distribution/Dynamic effect分类
天文与地球科学引用本文复制引用
陈斌,徐祥德,施晓晖..南亚高压对亚洲季风区夏季对流层上层水汽异常分布的动力效应[J].气象学报,2011,69(3):464-471,8.基金项目
国家科技部国际合作项目(2007DFB20210,2009DFB20540)、中国气象科学研究院基本科研业务费专项资金重点项目(2008Z006)、灾害天气国家重点实验室自主研究项目(2008LASWZI04、2009LASWZF02). （2007DFB20210,2009DFB20540）
