WRF modeling of the UTLS region of the July 29 2016 summer monsoon storms in China and comparison with aircraft and satellite observations

Deep convective storms represent the fastest vertical transport mechanism of both momentum and chemical species from the surface to the middle atmosphere, and these transports may potentially impact strongly the global atmospheric and climate processes. For example, the water vapor transported through the tropopause into LS may exert substantial radiative forcing due to its strong capability in intercepting terrestrial IR. Due to the difficulty in the in situ observation in the storm top region, most previous studies rely on remote sensing data whose interpretation can be ambiguous. Consequently, many details of the transport process remain unclear. On July 29, 2016, we encountered a line of convective storms along the coast of China from about Lat 35°N to Lat 22°N during a flight onboard of a commercial aircraft and made many photographic records of the storm tops that exhibited strong internal gravity wave (IGW) features. The visible satellite images of these coastal storms were retrieved from Himawari-8 archive and made into a loop. The simultaneous availability of both aircraft and satellite observations makes this episode a rare case for improving our understanding of the UTLS dynamics.

We performed WRF simulation of this case with a domain as illustrated in Fig. 1(a) and the results compare favorably with the satellite observations. We are analyzing the results to understand especially the vertical structure and the IGW, thermodynamics and mass transfer processes in the UTLS region (Fig. 1(b)). We will use the aircraft and satellite observations to substantiate the model interpretation of the storm top processes. The animations of model results and satellite loops provide a clear picture of deep convection dynamics in UTLS. We will also discuss the potential global impact of these processes.