资源环境科技发展态势分析平台

Common biases of climate models in simulating sea surface temperature (SST) greatly limit our understanding of future climate change. The cold SST bias in the northwestern Pacific (NWP), one of the most distinct and persistent biases in all generations of climate models, was previously attributed to the local and remote influences of the Pacific and Atlantic Oceans, but has never been related to the Indian Ocean. By analyzing simulations from 52 state-of-the-art CMIP6 models and a series of model experiments, we find the strong cold bias in the NWP is primarily caused by the weak cold bias in the tropical Indian Ocean (TIO). Eliminating the TIO bias induces a prominent pressure high over the NWP, which favors a SST warming there through the enhancement of warm oceanic Ekman advection. Our results indicate that the large NWP cold bias could be reduced by ∼66% once the weak TIO bias is corrected.