The Third Pole (TP), which refers to the Tibetan Plateau and its surrounding regions, is the highest and most extensive upland region in the world. The Tibetan Plateau is termed as TP given its ice fields contain the largest reserve of freshwater outside the two polar regions (Arctic and Antarctica). Changes in the water cycle over the TP may affect more than 20% of the world population since several major Asian rivers originate from the TP. The TP has experienced a warming rate of twice as fast as the rest of the world. Under the warming, the number of lakes, with an area larger than 1 km2, has increased together with expanded wetlands. It is of great interest to investigate the feedback of changes in lakes and wetlands on precipitation over the TP. Further, due to the complex terrain, coarse-resolution simulations cannot well capture the impact of topography on the local circulation and precipitation over the TP. Due to the harsh environment, ground-based observations are scarce. The available limited observations are mostly located over valleys. The observation can only resemble the climate condition of a small area. Fine-resolution (< 4 km) model simulations are then required, which are more comparable with observations than coarse-resolution simulations. In this project, the Advanced Research version of the Weather Research and Forecasting model (WRF-ARW) will be used with horizontal resolution <=4km, which is also called convection-permitting modeling (CPM). Results from the previous NAISS project (see Activity Reports) have shown that CPM, especially an ensemble of CPMs, can well capture the warm-season precipitation metrics compared with ERA5, including most wet-day and hour statistics. However, we can also see that the current CPM has limited ability to simulate extreme precipitation downstream of the TP, such as the Sichuan Basin. The results are just from one year of simulation and some case studies. Further study is needed to examine the ability of CPM simulations to capture precipitation statistics as well as extreme events under different climate backgrounds, such as in different years. The model simulation could be improved by better capturing land-atmosphere interaction. To do this, we plan to conduct a decadal-long simulation (e.g., 2015-2024) using the WRF to better understand the CPM models’ ability to reproduce summer precipitation over the TP. Further, we will also plan to conduct CPM simulations with improved land cover data sets, which may help to understand how to improve the CPM simulations over the TP regarding precipitation simulation. The outcomes of the project are expected to enhance our understanding of recent changes in precipitation and water resources over the TP. Studies on the water cycle will also benefit tremendously from the results of this project. This project is the Swedish contribution to WCRP-CORDEX Flagship Pilot Studies (FPS) about high-resolution climate modeling over the TP (http://rcg.gvc.gu.se/cordex_fps_cptp/).