| The distributions and variations of atomosphere water vapor in upper troposphere– lower stratosphere (UT/LS) play an important role in the radiation energy balance of global earth-atmosphere, therefore exert an greatly affect on global climate changes. Asian monsoon region is a"window"of water vapor transport and exchange between troposphere and stratosphere in Northern Hemisphere in summer. As an important physical process to affect water vapor and other trace gases of UT/LS, the mass transport and exchange over this area has been focused on, but till now the research is at its early stage.Therefore, in this paper, based on the synthesis analysis of updata satellite products, related observation and re-analysis data, etc., and by utilizing lagrangian FLEXPART model, the method of combining diagnostic analysis with numerical simulation, the process to transport water vapor transport from troposphere to stratosphere and associated possible mechanism in summer over Asian monsoon region are studied. Several conclusions are listed as followings:(1)Multiyear re-analysis data show that, Tibetan plateau and its peripheral areas in Northern Hemisphere is controlled by strong south asian high in summer season. The air temperature wave pattern in UT/LS area show that the temperature changed can transfer from UT to LS verticaly. Compare to the same latitudeal areas, this region has the highest tropopause height, which is often lower than 100 hPa in summer. The strongest ascent motion is located at the southeast side of the south asian high. The climatology feature of atmospheric stream field provides favorable circumfluence background condition for TST. (2)The intra-seasonal oscillation characteristics of UT/LS atmosphere components in asian monsoon in summer are analyzed by utilizing the tested reversion data collected from Microsoft Limb Sound(MLS) and Atmospheric Infrade Sounder (AIRS). It is found that two osillation periods role for UT atmosphere components changes, i.e., 10-20 dyas and 30-60 days, while the intra-seasonal oscillation period for LS is 30-60 days. These two periodic oscillations are in phase with the convective heating above Tibetan plateau and its southern area in summer, and the location changes of south asian high, respectively. It indicates that, the convection over Tibetan plateau and its surrounding regions in summer, and the south asian high are two main dynamical processes to affect the TST transport of UT/LS atmosphere.(3)The diagnostic analysis of troposphere stratosphere mass exchange(STE) shows that TST mainly presents in the southeast side of Tibetan plateau, and its surrounding UT/LS height. Satellite products also indicate the areas controled by south Asian high is the mainly transport pathway of TST. By computing the residence time of air particles, two sinks of TST transport across the tropopause are found: one is tropical, the other is high-latitude region. It illuminates that the TST process in UT/LS region above Tibetan plateau where the south asian high is the main atmosphere circulation feature has great influence on global STE.(4)In this paper, the effect of south asian high in the UT/LS trace distribution and transportation also be studied. Idealized ensemble numerical simulation illuminates the influence of south asian high on the anomaly distribution of trace gases mostly in the height between 14km and 16km. It takes about 3-6 days to transport air contamination from near-surface layer upwards to the lower troposphere near south asian high region vertically. While in horizontal direction, the close circumfluence of south asian high makes near-surface-layer air contamination stay inside the anticyclone about more than one month. It indicates that short-lifecycle photochemical reaction process of air contamination may also affect the lower-troposphere atmosphere components. This may be one of the explanaitons for which the low-value center of ozone and anomaly distribution characteristics of other atmosphere components present above Tibetan plateau in summer. (5)Back trajectories driven by large-scale analyzed wind fields are used to investigate the mainly water vapor convective soure which can contribute to the water balance in asian summer monsoon UT/LS region, as well as the air mass sources for tropospher to stratospher mass transport (TSMT), defined in terms of the locations where each trajectory last left the atmospheric boundary layer. Results show us that the mainly mass source is different from of the water vapor. The tropical western Pacific Ocean, the bengal bay, India areas, the south of Tibetan plateau and its adjoints are the main mass convective sources, which is consistent with the horizontal distribution of near-surface-layer summer convection. While the Tibetan plateau and its surrounding areas is the most important water vapor source for LS. Streathen convection over this area and the more warm tropoapause temperature can be used to explain this phenomena.(6) By combined the meso-scale weather forcast model and the lagrangian transport model, this paper presented a study on the process and possible mechanism of the vapor transport from near PBL to LS in the south Asian monsoon anticycloon. The mositened air can be lifted to the 320-340K potential temperater levels firstly, and then transport toward North-West conved by largen scale advection. The air parcels experienced their cold point temperature at the east and south part of the anticycloon and then be transported into strotospher. The maxmium water vapor in UTcan be exist and transported into stratosphere mainly due to not the convection moisten but the anticycloon large scale advection.
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