MJO Features and Teleconnection Changes under Global Warming

(CESM2 large ensemble's agreement on MJO teleconnection changes)

The Madden–Julian Oscillation (MJO) is the dominant mode of tropical intraseasonal variability, shaping global weather and climate through its teleconnections (e.g., Stan et al. 2017). Changes in MJO behavior, in the past and future, can substantially alter precipitation across extratropical regions spanning the Americas, East Asia, Australia, and Europe. Using multiple climate models, we show that MJO propagation speed increases under warming, with the acceleration weakening at later warming stages, and that teleconnections to the Southwest and Southeast US strengthen accordingly. These changes are driven largely by increased mean static stability and column moisture, the competition between the two, and the expansion of the warm pool under global warming.

Related works: Cui and Li (2019), Cui and Li (2022), and Cui & Maloney (2026)

Westerly Wind Events & Oceanic Kelvin Waves in the Equatorial Pacific

(Schematics of the connections between WWE, OKW, and ENSO)

(Example of an identified WWE and its OKW response)

Eastward-propagating oceanic Kelvin waves (OKWs), typically triggered by westerly wind events (WWEs) over the equatorial warm pool, modulate upper-ocean thermal structure and feed back onto coupled air-sea phenomena such as El Niño onset. My research uses newly available daily thermocline depth fields from CMIP6 models to ask how well these processes are captured in climate simulations: whether WWEs and OKWs are realistically represented, how faithfully models reproduce their air-sea coupling, and what role upper-ocean biases play where discrepancies arise.

Related works: Riley Dellaripa et al. (2024), Cui et al. (2024), and Cui et al. (2025)