The North Tropical Atlantic (NTA) is a leading mode of tropical interannual variability. NTA warming shifts the Atlantic intertropical convergence zone (ITCZ) northward, manifesting itself as enhanced rainfall in the Northern Hemisphere (NH) and reduced rainfall in the Southern Hemisphere (SH), thereby driving broad climatic impacts worldwide. However, the ability of climate models to simulate the NTA’s influence on the ITCZ remains unclear. Here, we evaluate the performance of 34 AMIP and coupled models from phase 6 of the Coupled Model Intercomparison Project (CMIP6). In AMIP, most models simulate eastward-displaced SH anomalies. For the NH anomalies, although the multi-model ensemble mean reasonably reproduces the observed location, individual models exhibit larger biases. In CMIP, model biases are larger than those in AMIP: 9 of 34 (26%) models fail to reproduce the northward ITCZ shift, and most of the remaining models simulate a southeastward displacement in both anomalies. In both atmospheric and coupled models, these location biases are closely related to those in rainfall climatology, whereas biases in simulating the NTA spatial pattern play a limited role in CMIP.

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