70 Years of Development in China’s Operational Numerical Weather Prediction System

Numerical weather prediction (NWP) is the core technology of weather forecast and disaster prevention and mitigation. The research and operational applications of NWP have always been highly valued in China, and have achieved great achievements with broad international influence in the theories, methods and operational system developments. This paper first summarizes the scientific and technological progresses of NWP in China, and then focuses on the current status and recent progresses of two domestically developed NWP systems, i.e., GRAPES (Global Regional Assimilation and PrEdiction System) and YHGSM (YinHe Global Spectral Model). GRAPES implements deterministic and ensemble forecasting systems with autonomous technology ranging from regional 3-10 km to global 12-50 km resolutions. New breakthroughs have been made in dynamic core, four-dimensional variational assimilation and satellite data assimilation, etc. The GRAPES system also is extended to include the atmospheric chemistry model, typhoon numerical model and ocean wave model. YHGSM continues to follow the development route of spectral models, breaking through techniques such as dry-mass conserved spectral dynamical core, ensemble four-dimensional variational assimilation, coupled ocean-land-atmosphere ensemble forecast, and establishing a numerical forecast system with high resolution global medium-term and monthly extension numerical forecast as the core. The NWP systems independently developed by the army and the government is the result of long-term adherence to the established science and technology direction, the close combination of academic research and operation development.