Decrease of Sensible Heat Flux over the Tibetan Plateau: Numerical Simulation

Many studies have found that sensible heat flux over the Tibetan Plateau (TP) exhibits a significant decreasing trend since the 1980, and the weakening of sensible heat flux is related to the reduction of surface wind speed over the TP. Further research suggests that the decreasing trend in sensible heat flux is primarily a response to the greater warming at mid- and high latitudes than over the tropics and subtropics. Using the Advanced Research Weather Research and Forecasting model, numerical experiments were conducted to demonstrate how the greater warming at mid- and high latitudes can alter the climate in the TP. The model was setup with two interactive nested domains. The inner domain covers the TP region at a spatial resolution of 9 km. The simulation was integrated by fixing the solar radiation on August 1^st. The control runs effectively simulate the distribution of sensible heat flux over the TP, with larger sensible heat flux in the western region of the TP. In the sensitivity experiments with greater warming at mid- and high latitudes, most observed trends can be simulated including decrease of sensible heat flux over the TP (Fig. 1). This study demonstrates that the observed climate changes over the TP result from the greater warming at mid- and high latitudes, which is related to global warming.