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Increase in convective extreme El Nino events in a CO₂ removal scenario.

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 CO₂ 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 CO₂ forcings.

SUBMITTER: Pathirana G

PROVIDER: S-EPMC10284559 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Increase in convective extreme El Niño events in a CO2 removal scenario.

Pathirana Gayan G Oh Ji-Hoon JH Cai Wenju W An Soon-Il SI Min Seung-Ki SK Jo Seo-Young SY Shin Jongsoo J Kug Jong-Seong JS

Science advances 20230621 25

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 CO2 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 a ...[more]

PMID: 37343086

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