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Abstract Previous studies found many climate properties such as northern hemisphere (NH) surface temperature and precipitation respond non-monotonically when CO₂is increased from 1×to 8×CO₂relative to pre-industrial levels. Here, we explore the robustness of the non-monotonicity in the NH precipitation response in 11 coupled climate models. Eight models show a decrease in NH precipitation under repeated CO₂doubling, indicating that the non-monotonic response is a common but not universal result. Although common, the critical CO₂level where the NH precipitation decrease first occurs differs widely across models, ranging from 2×CO₂to 8×CO₂. These models also show a prominent weakening in the Atlantic meridional overturning circulation (AMOC) at the same critical CO₂level, with the AMOC weakening leading the precipitation decrease. The sensitivities of NH precipitation and the AMOC to CO₂doublings are positively correlated, especially when the AMOC weakens beyond 10 Sv. This suggests that the differences in models’ AMOC response can explain their contrasting NH precipitation responses, where models with a large AMOC weakening have decreased NH precipitation. Regionally, this decrease in NH precipitation is the most prominent over the North Atlantic, Europe and the tropical Pacific. Our results suggest that special care must be taken with the use of pattern scaling to inform regional climate decision-making.