Regional and Teleconnected Impacts of Solar Radiation-Topography Interaction Over the Tibetan Plateau

Solar radiation-topography interaction plays an important role in surface energy balance over the Tibetan Plateau (TP). However, the impacts of such interaction over the TP on climate locally and in the Asian regions remain unclear. This study uses the Energy Exascale Earth System Model (E3SM) to evaluate the regional and teleconnected impacts of solar radiation-topography interaction over the TP. Land-atmosphere coupled experiments show that topography regulates the surface energy balance, snow processes, and surface climate over the TP across seasons. Accounting for solar radiation-topography interaction improves E3SM simulation of surface climate. The winter cold bias in air temperature decreases from -4.57 to -3.79 K, and the wet bias in summer precipitation is mitigated in southern TP. The TP's solar radiation-topography interaction further reduces the South and East Asian summer precipitation biases. Our results demonstrate the topographic roles in regional climate over the TP and highlight its teleconnected climate impacts. The Tibetan Plateau (TP) is characterized by high elevation and complex topography. Interaction between solar radiation and the undulating topography has important impacts on the regional surface energy balance and hydrologic cycle. Here we use Earth System Model simulations to show the local and remote impacts of the TP's solar radiation-topography interaction on the surface climate of the Asian regions. Such interaction overall increases the air temperature especially in winter over the TP and reduces the summer precipitation in southern TP. Teleconnectedly, the interaction further alters the precipitation patterns in South and East Asia, by altering the atmospheric circulation that influences moisture transport and clouds. Accounting for such interaction generally improves the model performance when benchmarked against observations. These findings underscore the important roles of the TP's solar radiation-topography interaction in modulating the climate of the local and remote Asian regions. Solar radiation-topography interaction over the Tibetan Plateau (TP) increases annual average regional near-surface air temperature by 0.26 KSolar radiation-topography interaction over the TP also affects the precipitation patterns in South and East AsiaIncluding solar radiation-topography interaction improves the simulation of surface climate over the TP and Asian regions

Automated summary

Solar radiation-topography interaction plays important roles in the climate of the Tibetan Plateau and Asian regions. It regulates the surface energy balance, snow processes, and surface climate over the Tibetan Plateau. Considering this interaction improves the simulation of surface climate, reducing the winter cold bias and mitigating the wet bias in summer precipitation.