Open AccessClimatological perspectives of air transport from atmospheric boundary layer to tropopause layer over Asian monsoon regions during boreal summer inferred from Lagrangian approach
Author(s) -
Bin Chen,
Xiangde Xu,
Shuai Yang,
Tianliang Zhao
Publication year - 2012
Publication title -
atmospheric chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.622
H-Index - 206
eISSN - 1680-7324
pISSN - 1680-7316
DOI - 10.5194/acp-12-5827-2012
Subject(s) - troposphere , climatology , tropopause , environmental science , monsoon , atmospheric sciences , plateau (mathematics) , boreal , bengal , east asian monsoon , monsoon of south asia , hysplit , stratosphere , bay , geology , geography , meteorology , aerosol , oceanography , mathematical analysis , mathematics , paleontology
The Asian Summer Monsoon (ASM) region has been recognized as a key regionthat plays a vital role in troposphere-to-stratosphere transport (TST),which can significant impact the budget of global atmospheric constituentsand climate change. However, the details of transport from the boundarylayer (BL) to tropopause layer (TL) over these regions, particularly from aclimatological perspective, remain an issue of uncertainty. In this study,we present the climatological properties of BL-to-TL transport over the ASMregion during boreal summer season (June-July-August) from 2001 to 2009. Acomprehensive tracking analysis is conducted based on a large ensemble ofTST-trajectories departing from the atmospheric BL and arriving at TL.Driven by the winds fields from NCEP/NCAR Global Forecast System, all theTST-trajectories are selected from the high resolution datasets generated bythe Lagrangian particle transport model FLEXPART using a domain-fillingtechnique. Three key atmospheric boundary layer sources for BL-to-TLtransport are identified with their contributions: (i) 38% from theregion between tropical Western Pacific region and South China Seas(WP) (ii) 21% from Bay of Bengal and South Asian subcontinent (BOB), and(iii) 12% from the Tibetan Plateau, which includes the South Slope of theHimalayas (TIB). Controlled by the different patterns of atmosphericcirculation, the air masses originated from these three source regions aretransported along the different tracks into the TL. The spatialdistributions of three source regions keep similarly from year to year. Thetimescales of transport from BL to TL by the large-scale ascents r-rangefrom 1 to 7 weeks contributing up to 60–70% of the overall TST,whereas the transport governed by the deep convection overshooting becomefaster on a timescales of 1–2 days with the contributions of 20–30%.These results provide clear policy implications for the control of veryshort lived substances, especially for the source regions over Indiansubcontinent with increasing populations and developing industries