Abstract:
The Tibetan Plateau, known as the "Roof of the World" and the "Third Pole," plays a significant role in regional climate, East Asian climate, and even global climate due to the thermal and dynamic forcing mechanisms generated by its unique terrain. Against the backdrop of worsening global warming, the Tibetan Plateau is characterized by an obvious warming and wetting trend, with frequent occurrences of extreme heat and precipitation events. Simultaneously, there has been a notable reduction in snow cover, leading to glacier retreat, accelerated permafrost thawing, and shortened soil freezing periods, which are accompanied by more frequent meteorological and related disasters and attract widespread attention from the international community and scientific community. However, global climate simulations for the Tibetan Plateau show considerable uncertainties. Due to the plateau's complex terrain, global climate models, with their coarse spatial resolution and rudimentary representation of physical processes, cannot accurately capture mesoscale and microscale weather and climate effects. Compared to global climate models, regional climate models have higher spatial resolutions that can better describe detailed regional terrain features such as local topography and surface conditions, and thus can more effectively simulate regional climate characteristics. With advances in computational resources and supercomputing capabilities, the horizontal resolution of regional climate simulations has been improved to the convective-permitting scale, and model simulation errors are greatly reduced. This paper first introduces discussions and evaluations of resolution in regional climate simulations over the Tibetan Plateau, noting that increasing horizontal resolution of regional climate models can indeed improve the accuracy of simulations of climate characteristics over the plateau, especially in regions with complex terrain and frequent convective activities. However, comprehensive and objective evaluations are still needed. Additionally, the paper discusses improvements in model physical processes from perspectives of land surface, cloud cover, and microphysics schemes. Finally, it addresses the challenges and future directions in regional climate simulation over the Tibetan Plateau.