Progresses in the Study of the Climate Impacts of the Elevated Heating over the Tibetan Plateau
青藏高原抬升加热气候效应研究的新进展

The progresses of study of the climate impacts of the Tibetan Plateau heating over the past lour years arc reviewed. Firstly, based on the potential vorticity (PV) equation and the theory of therm al adaptation, the mechanism for the formation and maintenance of the circulations over the Tibetan Plateau in summer are explored. Result shows the positive PV that is produced by heating near the sur face is balanced by the frictional dissipation, and the negative PV that is generated by heating in the up per layers over Tibetan Plateau is balanced by the divergence of negative PV. It is further substantiatedthat the sensible heating plays important roles in the seasonal transition of atmospheric circulation from winter to summer and in the Asian monsoon onset. The evolution of diabatic heating over the Tibetan Plateau causes the variation in land-sea thermal contrast, and results in the earliest breaking of the subtropical anticyclone belt and Asian monsoon onset over the eastern Bay of Bengal. The results also suggest that the spatial and temporal evolution of the vertical shear of zonal wind can better reflect the territorial differences in seasonal variability. The strong (weak) diabatic heating over the Tibetan Pla teau in summer corresponds to the high (low) efficiency of the Sensible Heal driven Air Pump (SHAP) over the plateau, and result in strong (weak) divergence in the upper troposphere and convergence in the lower troposphere. Furthermore, the northeastward propagating Rossby wave train induced by the anomalous heating over the Tibetan Plateau can reach far distance areas. Therefore, the interannual va riability of the diabalic heating over the Tibetan Plateau is closely correlated with that of the in-situ and north hemispheric circulations. Finally, it was reported that in summer, there exists bimodality in the longitude location of the South Asian High in the upper troposphere: the Tibetan mode and Iran mode. Such bimodalily is closely associated with the thermal states of the Tibetan Plateau, and significantly affects the climate anomalies over the Asian monsoon area in summer.