Projection and Uncertainty of Midsummer Precipitation in the Northern China Monsoon Region by CMIP6 Models

ABSTRACT

Based on 30 CMIP6 global climate models and observational data from 2374 meteorological stations in China during 1961–2020, the primary objective of this study is to investigate the sources of uncertainty in model projections from both thermodynamic and dynamic perspectives. The projection of mid‐summer precipitation trend is slight increasing in the near‐term (2021–2040), maximum in the mid‐term (2041–2060) and slowing down in the long‐term (2081–2100) over northern China monsoon region (NCMR), and its mean increasing trend is projected to be 3% (5%) under different scenarios in the near‐term (mid‐term), and slightly decreases to 2% in the long‐term. Especially, it is sensitive to temperature change under shared Socioeconomic Pathway 1‐2.6 (SSP1‐2.6). Optimal model simulations show that the dynamic term dominates the increase in NCMR midsummer precipitation, while the thermodynamic term contributes negatively, offsetting some of the dynamic‐induced rise. Therefore, it is highly likely that the dynamic term dominates the future increase in precipitation over the NCMR and is also the primary factor contributing to discrepancies in results among different models.