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Existing studies contend that latent heating (LH) will replace sensible heating (SH) to become the dominant factor affecting the development of the Tibetan Plateau vortex (TPV) after it moves off the Tibetan Plateau (TP). However, in the process of the TPV moving off the TP requires that the airmass traverse the eastern slope of the Tibetan Plateau (ESTP) where the topography and diabatic heating (DH) conditions rapidly change. How LH gradually replaces SH to become the dominant factor in the development of the TPV over the ESTP is still not very clear. In this paper, an analysis of a typical case of a TPV with a long life history over the ESTP is performed by using multi-sourced meteorological data and model simulations. The results show that SH from the TP surface can change the TPV-associated precipitation distribution by temperature advection after the TPV moves off the TP. The LH can then directly promote the development of the TPV and has a certain guiding effect on the track of the TPV. The SH can control the active area of LH by changing the falling area of the TPV-associated precipitation, so it still plays a key role in the development and tracking of the TPV even though it has moved out of the main body of the TP. [ABSTRACT FROM AUTHOR]

The South Asian summer monsoon (SASM) is a significant monsoon system that exerts a profound impact on climate and human livelihoods. According to 38 models from the Coupled Model Intercomparison Project Phase 6, the SASM circulation is projected to weaken significantly under global warming as seen in the weakened low-level westerly wind over the northern tropical Indian Ocean; however, the associated climate dynamics is still under debate. Here, we identify that the weakened low-level westerly wind is closely related to the enhanced latent heating over the Tibetan Plateau (TP), which corresponds with increased summer precipitation in the future. The intensified TP latent heating triggers an anomalous meridional circulation with ascending motions over the plateau and descending motions to the south, leading to an anomalous low-level anticyclone over the northern tropical Indian Ocean. This anticyclone greatly weakens the prevailing low-level westerlies of the SASM through easterly anomalies at the anticyclone's southern flank. Moisture budget analysis further reveals that increased atmospheric water vapor, rather than the vertical dynamic component, makes the largest contribution to the increased precipitation over the TP. This result confirms that the enhanced TP latent heating is a driver of atmospheric circulation change and contributes to weakening the SASM circulation. [ABSTRACT FROM AUTHOR]