Increase in convective extreme El Niño events in a CO <sub>2</sub> removal scenario
Ullala Pathiranage Gayan Pathirana, Ji‐Hoon Oh, Wenju Cai, Soon‐Il An, Seung‐Ki Min, Seo‐Young Jo, Jongsoo Shin, Jong‐Seong Kug
Abstract
Convective extreme El Niño (CEE) events, characterized by strong convective events in the eastern Pacific, are known to have a direct link to anomalous climate conditions worldwide, and it has been reported that CEE will occur more frequently under greenhouse warming. Here, using a set of CO 2 ramp-up and ramp-down ensemble experiments, we show that frequency and maximum intensity of CEE events increase further in the ramp-down period from the ramp-up period. These changes in CEE are associated with the southward shift of the intertropical convergence zone and intensified nonlinear rainfall response to sea surface temperature change in the ramp-down period. The increasing frequency of CEE has substantial impacts on regional abnormal events and contributed considerably to regional mean climate changes to the CO 2 forcings.