Previous studies have indicated that the sucking and pumping effects induced by surface sensible heating (SH) lead to vigorous ascent and moisture convergence over the southern Tibetan Plateau (TP), which is the primary cause of local precipitation formation. Numerical simulations with the Weather Research and Forecasting (WRF) model show that weak ascending motion and precipitation still exist over the southern slope of the TP when local surface SH is suppressed and that this precipitation is associated with microphysical processes. Suppressed surface heating induces a significant cold anomaly near the surface, which reduces the saturation-specific humidity but increases relative humidity. The process of the phase change of moisture results in the formation of obvious microphysical large-scale precipitation. Moreover, latent heating is released due to microphysical condensation corresponding with the phase change process, which further leads to a weak ascending and convective precipitation over the southern slope of the TP. Thus, local precipitation over the slope when surface heating is suppressed results directly from large-scale condensation precipitation and indirectly from the convective precipitation induced by the microphysical processes of moisture phase change, instead of the sucking and pumping effects due to the surface heating of the TP.
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