Towards Ensemble-Based Kilometer-Scale Climate Simulations over the Third Pole Region

The Tibetan Plateau and its surrounding mountains have an average elevation of 4,400 m a glaciated area $$\sim $$ 100,000 $$\hbox {km}^{2}$$ giving it the name “Third Pole (TP) region”. TP is headwater many major rivers in Asia that provide fresh water to hundreds millions people. Climate change altering energy cycle at record pace but future this region highly uncertain due challenges simulating weather climate processes complex area. Convection-Permitting Third (CPTP) project Coordinated Regional Downscaling Experiment (CORDEX) Flagship Pilot Study (FPS) aims revolutionize our understanding impacts on through ensemble-based, kilometer-scale modeling. Here we present experimental design first results from multi-model, multi-physics ensemble simulations three case studies. five participating modeling systems show high performance across range meteorological situations are close having ”observational quality” precipitation near-surface temperature. This partly large differences between observational datasets region, which leading source uncertainty model evaluations. However, systematic cold bias above 2000 exists most systems. Model physics sensitivity tests performed with Weather Research Forecasting (WRF) planetary boundary layer (PBL) microphysics contribute equally uncertainties. Additionally, larger domains result better performance. We conclude by describing high-priority research needs next steps CPTP project.