A recent study 17 found that in the Coupled Model Intercomparison Project (CMIP) version 6, an El Niño-like eastern Pacific warming reduced North American monsoon rainfall as a result of the equatorward shift of the intertropical convergence zone. However, a few studies have suggested that the signal for consistent strengthening was relatively weak across the models 17, 20, 22, although the multimodel ensemble mean showed robust increases in ENSO-induced precipitation. Previous studies have discussed future changes in precipitation anomalies induced by projected ENSO in East Africa 16, 19, 20, 21, 22, the Maritime continent 23, 24, 25, South and East Asia 17, 19, 26, North America 18, 19, 20, and major monsoon regions 17, 19 based on enhanced ENSO-teleconnection under anthropogenic forcings. These results suggest the presence of considerable uncertainty in the prediction of future changes with regard to El Niño diversity 8, 10, 15.ĮNSO-driven tropical precipitation anomalies are projected to increase significantly under the high emission scenario proposed by the Intergovernmental Panel on Climate Change 16, 17, 18. In contrast, other studies have shown a more frequent occurrence of eastern Pacific (EP) El Niño events 9, 14 and stronger sea surface temperature (SST) variability in the eastern Pacific under greenhouse warming 9, 12, 13. A few studies have shown an increased frequency of central Pacific (CP) El Niño events 8, 11. However, the intermodel spreads of the projected future change of ENSO are relatively large 10, 12. Many studies have reported that ENSO’s intensity and frequency might increase under greenhouse warming 9, 10, 11, 12, 13. Our findings highlight the importance of the mean SST projection in selectively influencing the types of El Niño and their remote impact on precipitation.Ĭonsidering the severe impact of the El Niño-Southern Oscillation (ENSO) on global 1, 2 and regional weather 3, 4, 5, 6, climate 2, 3, and society 1, 2, the improvement in the reliability of future projections of El Niño events and uncovering their underlying mechanism is of great importance to the climate science community 7, 8, 9, 10, 11. Meanwhile, an El Niño-like mean SST change generates more frequent eastern Pacific El Niño events, enhancing precipitation in North American. A La Niña-like mean SST change intensifies basin-wide El Niño events causing approximately 20% more precipitation over East Asia and North America via enhancing moisture transport. Here, by analyzing the Coupled Model Intercomparison Project simulations, we show that future precipitation changes are tightly linked to the response of each type of El Niño to the tropical Pacific mean sea surface temperature (SST) change. However, thus far, consensus is lacking regarding future changes in mid-latitude precipitation influenced by El Niño. This demands an advanced understanding of the changes in El Niño-induced precipitation under the future global warming scenario. El Niño profoundly impacts precipitation in high-population regions.
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