Different climate response persistence causes warming trend unevenness at continental scales

Global warming exhibits distinct differences at continental scales, yet whether models capture these differences is unclear. Here, we show that Coupled Model Intercomparison Project Phase 6 climate models underestimate warming unevenness for China and the United States, possibly leading to a biased estimation of anthropogenic influence on warming over the two regions. Observational records suggest that the surface air temperature warming trends over China are 1.53 ± 0.10 and 1.38 ± 0.12 times those of the United States for 1900–2017 and 1951–2017, respectively. We find that surface air temperature changes over China seem more sensitive to external forcing owing to stronger long-range persistence, leading to substantially different warming trends between China and the United States. Our study provides insight into the drivers of contemporary climate warming that could help in devising climate change adaptation and mitigation strategies for the future.