Relation between Inter-annual Variation of the South Asian High Location and Precipitation over the Qinghai-Xizang Plateau in Summer

Abstract

Using synthetic analysis， dynamic diagnosis and numerical simulation， the relation between South Asian High （SAH） Location and Precipitation over the Qinghai-Xizang Plateau （QXP） in summer at inter-annual scale is analyzed， characteristics and effects of water vapor transport and diabatic heating over QXP are diagnosed.Results show that， when SAH shifts to southeast （northwest）， water vapor convergence （divergence） and water vapor transport over the eastern QXP are significant， while water vapor divergence （convergence） over the southwestern QXP is significant， which are the key factors that result in significant more （less） precipitation on eastern QXP and significant less （more） precipitation on southwestern QXP.The anomalous atmospheric condensational latent heating on eastern QXP contributes to the maintenance of the relation between the location of SAH and precipitation over QXP.When SAH shifts to southeast （northwest）， precipitation over northwestern QXP is significantly increased （decreased）， which is related to the stronger （weaker） surface latent heating and the lower （higher） geopotential height at lower atmosphere in this region， however， this relation is not significant.

Keywords

• qinghai-xizang plateau （qxp）
• summer precipitation
• south asian high
• inter-annual variation