A physically-refined regional climate model for the Tibetan Plateau

Area of Science:

• Climate Science
• Atmospheric Science
• Environmental Science

Background:

• Accurate climate modeling of the Tibetan Plateau (TP) is crucial for understanding Asian monsoon variability, water resources, and energy cycles.
• Existing models struggle with TP's complex climate, often showing significant overestimations of precipitation and underestimations of cold-season temperatures.

Purpose of the Study:

• To introduce the Tibetan Plateau Climate System Model (TPCSM), developed from the WRF model, with enhanced physical processes.
• To improve the accuracy of climate simulations for the Tibetan Plateau region.

Main Methods:

• Enhanced or incorporated key physical processes including terrain, land, lakes, snow, and clouds.
• Implemented a turbulent orographic form drag scheme and a probability cloud fraction scheme.
• Improved parameterizations for shallow-snow albedo and complex terrain effects on snow cover.

Main Results:

• Reduced summer precipitation wet bias from 2.0 to 0.5 mm/d.
• Nearly eliminated cold bias in winter-to-spring air temperature, improving from -1.8°C to 0.1°C.
• TPCSM has been used in international projects and for developing high-resolution meteorological datasets.

Conclusions:

• The TPCSM represents a significant advancement in regional climate modeling for complex terrain.
• Improved simulations enhance understanding of TP's water and energy cycles.
• Findings have implications for water resource management, hazard forecasting, and climate change impact assessment in the Third Pole region.