Moist convection and tracer transport in and out of the Asian Summer Monsoon Anticyclone

The Asian Summer Monsoon Anticyclone (ASMA) plays a critical role in trapping, transporting, and redistributing water vapour in the upper troposphere and lower stratosphere, particularly into the extratropical lower stratosphere. Comparison of ERA5 reanalysis data with remote sensing data and simulations with the model ICON-CLM in convection-parameterized (12 km grid spacing) and convection-permitting (3.3 km) setups indicate that the transport into the ASMA is overestimated in ERA5 over the Tibetan plateau (Singh & Ahrens 2023). This presentation critically discusses the water vapour transport into the upper-troposphere/lower-stratosphere by deep convective events over the Tibetan plateau and the Himalayas – an area identified as hotspot for troposphere-stratosphere exchange (Škerlak et al. 2014) using convection-parameterized reanalysis data. Our investigations use a decade-long ICON-CLM climate-like simulation (Collier et al. 2024) performed as a contribution to the CORDEX flagship pilot study Convection-Permitting Third Pole (CPTP).

References

Collier, E., N. Ban, N. Richter, B. Ahrens, D. Chen, X. Chen, H-W. Lai, R. Leung, L. Li, T. Ou, P.K. Pothapakula, E. Potter, A. F. Prein, K. Sakaguchi, M. Schroeder, P. Singh, S. Sobolowski, S. Sugimoto, J. Tang, H. Yu, C. Ziska: The First Ensemble of Kilometre-Scale Simulations of a Hydrological Year over the Third Pole. Clim Dyn. https://doi.org/10.1007/s00382-024-07291-2, 2024

Singh, P., B. Ahrens: Modeling Lightning Activity in the Third Pole Region: Performance of a km-Scale ICON-CLM Simulation. Atmosphere, 14(11), 1655, DOI: 10.3390/atmos14111655, 2023

Škerlak, B., M. Sprenger, and H. Wernli: A global climatology of stratosphere–troposphere exchange using the ERA-Interim data set from 1979 to 2011. English. Atmospheric Chemistry and Physics 14 (2), 913–937. doi: 10.5194/acp-14-913-2014, 2014