A peer-reviewed modelling study found that tropical Pacific temperature patterns remained altered after carbon dioxide emissions stopped. Deep-ocean and Southern Ocean warming continued while northern surface temperatures adjusted faster. Researchers compared nine Earth system models with longer simulations from one model. Earlier emissions cessation limited the size of the simulated change.
The east–west temperature contrast across the equatorial Pacific remained weakened after carbon dioxide emissions stopped in one peer-reviewed modelling study. The researchers examined average ocean conditions separately from the year-to-year El Niño–Southern Oscillation, the linked tropical Pacific ocean and atmospheric cycle. The simulated mean-state shift persisted for centuries even as atmospheric carbon dioxide declined.[1]
The Southern Ocean and deep water kept warming while Northern Hemisphere surface temperatures adjusted faster. Researchers linked the unequal adjustment to tropical rainfall belts moving toward the equator, weaker trade winds and a flatter thermocline, the boundary between warmer surface water and colder depths. Changes in the amplitude of El Niño–Southern Oscillation were less consistent across models and varied over time.[1]
The analysis compared nine Earth system models with longer experiments using the ACCESS-ESM1-5 climate model. Those experiments branched between 2030–2060 and ran for 1000 years. Earlier emissions cessation limited the magnitude of the change. The detailed millennial mechanism rested on one model. Other greenhouse gases and aerosols were set to preindustrial levels while carbon dioxide emissions stopped, defining the idealized conditions of the simulations.[1]
