Large eddy simulation study on the mechanism of convection initiation in the lake region of the Tibetan Plateau

Applying observed surface parameters and atmospheric vertical profiles, our study simulated and analyzed the mechanism of shallow convective cloud triggering and deep moist convection development in the lake region of the Tibetan Plateau. The research found that lake breeze circulation not only aids in triggering convection but also has the ability to horizontally transport water vapor, creating favorable conditions for the transition from shallow cumulus convection to deep moist convection. These results suggested that future studies on energy and water cycles in the Tibetan Plateau should prioritize the lake regions. Lakes serve not only as a “water supply source” for the water cycle in the Tibetan Plateau but also have a unique mesoscale system—lake breeze circulation, which provides positive feedback for the development of convection, as well as for water and heat exchange between the atmosphere and the underlying surface. Additionally, previous studies indicated that the area of lakes in the Tibetan Plateau has increased in the past, and existing studies predict that this trend will continue. The findings of this paper indicated that the increase in lake area is related to an increase in precipitation, providing important references for research on the water cycle in the Tibetan Plateau under climate change.