[A-CG43] Multi-scale ocean-atmosphere interaction in the tropics

[ACG43-01] Global climate mode resonance due to rapidly intensifying El Niño-Southern Oscillation

★Invited Papers

*Malte F Stuecker¹, Sen Zhao¹, Axel Timmermann², Ja-Yeon Moon², Sun-Seon Lee², Rohit Ghosh³, Fei-Fei Jin¹ (1.University of Hawaii at Manoa, 2.IBS Center for Climate Physics, 3.Alfred Wegener Institute)

Keywords:ENSO, greenhouse warming, climate dynamics

The El Niño-Southern Oscillation (ENSO) impacts climate variability across the globe, including many other modes of variability, thereby constituting the key predictable climate signal on seasonal timescales. However, how ENSO dynamics, its predictability, and its impacts change under greenhouse warming remains debated with climate models exhibiting a wide range of responses. Here we show that a state-of-the-art high-resolution climate model projects a possible future for ENSO that would have far-reaching consequences. The model simulates that ENSO gradually becomes less stable in boreal spring due to both the net feedback and the atmospheric stochastic forcing becoming stronger, approaching criticality in the second half of this century. Consequently, ENSO amplitude increases, ENSO events become highly regular, and ENSO both energizes and synchronizes with many other oceanic and atmospheric modes of variability. This global climate mode resonance would have wide-ranging “whiplash impacts” on regional climate.