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Increasing atmospheric CO2 causes substantial spatial and seasonal changes in air temperature and precipitation through its radiative (RAD) and vegetation physiological (PHY) effects. However, it remains poorly understood on how these two effects impact the integrated climate zone shifts over China. Here, we disentangle the RAD and PHY effects on the shifts of Köppen‐Geiger climate zones from pre‐industrial to 4 × CO2 in China using nine Earth system models. We find that climate zone changes over approximately 56.1% of China, and PHY contributes 15.2% of such changes at 4 × CO2. PHY shifts regional climate to warmer and wetter classifications, shrinking (−42.8%) the arid zone distributions and promoting (26.8%) the tropical zone northward extensions. Our findings highlight the critical role of vegetation in reshaping the overall climate zone distributions, yet introduce potential risk to climate mitigation and adaptation. Plain Language Summary: Ongoing rise in atmospheric CO2 not only alters the magnitudes of temperature and precipitation, but also shifts their spatial and seasonal variations, reshaping climate zone distributions. Vegetation amplifies global warming and modulates precipitation through its physiological response (PHY) to rising CO2, but how this process affects the local climate zone shifts is understudied, especially in China. Using nine CMIP6 Earth system models, we find that climate zone undergoes shifts across 56.1% of China at 4 × CO2, and PHY contributes 15.2% of such changes. PHY aids the northward expansions of tropical and temperate zones, and generally shifts the regions to warmer and wetter climate from pre‐industrial to 4 × CO2. Importantly, PHY diminishes (−42.8%) the arid zone coverage, indicating an important role of vegetation to alleviate water stress in those regions. Strong PHY contributions to the total climate zone area changes caused by rising CO2 emerges in Shandong, Shanxi, Ningxia, Guangdong and Guangxi at 4 × CO2. Our results clarify the climate zone shifts at 4 × CO2 and unravel the role of vegetation physiological response on shifting future climate zone distributions in China, providing new perspective on the role of vegetation in climate system. Key Points: Climate zone shifts across 56.1% of land area in China at 4 × CO2, 15.2% of which is contributed by vegetation CO2 physiological forcingCO2 physiological forcing shifts the regions to a warmer climate through lifting temperature, expanding tropical zone northwardVegetation acts to shrink arid zone as precipitation increases through CO2 physiological forcing [ABSTRACT FROM AUTHOR]

In this study, CMIP6 and single model initial‐condition large ensemble (SMILE) simulations were applied to reveal possible changes in the spatial coverage (RSC) of summer extreme precipitation (≥99th percentile) in China. Four different approaches were applied to provide a comprehensive assessment of RSC changes. Results indicate that the trend of RSC in summer for the period 1961–2020 in China is underestimated by raw simulations of CMIP6 multi‐model ensembles. Further analyses suggest that the confidence in model simulations reflecting the observed change can be improved based on the two observation constraint approaches and SMILE‐based approach. In addition, the reliability of the spatial distribution can also be improved. Projection results indicate that the RSC of summer extreme precipitation increases consistently with the increment of global warming across the different approaches. Among them, the results based on observational constraints and the SMILE‐based approach show enhanced reliability and present larger RSC changes than by directly using CMIP6 ensembles. In conclusion, extreme precipitation in summer is expected to become more widespread in China as the level of global warming increases. Plain Language Summary: Extreme precipitation causes severe impacts on agriculture, economy, and human health. However, it is projected by models to change in China but with low consistency. Thus, this paper provides an assessment of the projected characteristics of the ratio of spatial coverage (RSC) for extreme precipitation in China combined with multiple evidence and approaches. CMIP6 and single model initial‐condition large ensemble (SMILE) simulations are applied. Four approaches based on the statistics principle and physical interpretability are conducted to comprehensively assess change in RSC. Results reveal that extreme precipitation will become more widespread in China. Among them, results based on observation constraint approaches and SMILE‐based approach, which show enhanced accuracy and reliability, present larger RSC than directly using CMIP6 ensembles. It indicates that extreme precipitation will be more widespread in China combined with multiple evidence and methods. This study provides some scientific foundation for climate mitigation and adaptation. Key Points: Observed trend in RSC in China increased significantly in summer for the period 1961–2020 but is underestimated by CMIP6 multi‐model ensemblesConfidence is improved based on observation constraint and SMILE‐based approaches to raw model simulationsExtreme precipitation in summer will become more widespread, as supported by multiple evidence lines and approaches [ABSTRACT FROM AUTHOR]