Climate Change over China in the 21st Century as Simulated by BCC_CSM1.1-RegCM4.0

Abstract

Driven by the global model, Beijing Climate Center Climate System Model version 1.1 (BCC_ CSM1.1), climate change over China in the 21st century is simulated by a regional climate model (RegCM4.0) under the new emission scenarios of the Representative Concentration Pathways—RCP4.5 and RCP8.5. This is based on a period of transient simulations from 1950 to 2099, with a grid spacing of 50 km. The present paper focuses on the annual mean temperature and precipitation in China over this period, with emphasis on their future changes. Validation of model performance reveals marked improvement of the RegCM4.0 model in reproducing present day temperature and precipitation relative to the driving BCC_CSM1.1 model. Significant warming is simulated by both BCC_CSM1.1 and RegCM4.0, however, spatial distribution and magnitude differ between the simulations. The high emission scenario RCP8.5 results in greater warming compared to RCP4.5. The two models project different precipitation changes, characterized by a general increase in the BCC_CSM1.1, and broader areas with decrease in the RegCM4.0 simulations.

Keywords:

• climate change
• regional climate model
• RCP scenarios
• China