Atlantic Niño, a significant climate mode in the equatorial Atlantic, exerts remote influence on the Pacific, inducing a La Niña-like response. This study uses observations and large-ensemble simulations to investigate the underlying mechanisms. An eastward-propagating atmospheric Kelvin wave, traveling from the Atlantic through the Indian Ocean to the Pacific, is identified as the primary pathway. The Maritime Continent's orography contributes to orographic moisture convergence, facilitating the formation of a local Walker Cell. Land friction over the Maritime Continent dissipates Kelvin wave energy, influencing the Bjerknes feedback and the La Niña-like response's strength. Improved representation of land-atmosphere-ocean interactions over the Maritime Continent is crucial for accurate simulation of Atlantic Niño's impact on El Niño-Southern Oscillation (ENSO).

Siying Liu, Ping Chang, Xiuquan Wan, Stephen G. Yeager, Ingo Richter