Background trade winds and climate sensitivity control the eastern equatorial Pacific warming pattern.

Background trade winds and climate sensitivity primarily determine the magnitude of eastern equatorial Pacific warming, explaining about 74% of model variability by the late 21st century.

• Why it matters: Understanding what drives the variability in Pacific warming patterns is crucial for predicting climate impacts and improving model accuracy, especially for El Niño-related phenomena.
• What they did: The study analyzed climate models and conducted perturbation experiments to assess how background trade winds and effective climate sensitivity influence sea surface temperature contrasts and feedback mechanisms.
• The result: Findings suggest that stronger trade winds and higher climate sensitivity amplify feedbacks, leading to a significant reduction in the zonal SST gradient, which constrains future climate change projections.