Super El Niños in response to global warming in a climate model
Extraordinarily strong El Niño events, such as those of 1982/1983 and 1997/1998, cause havoc with weather around the world, adversely influence terrestrial and marine ecosystems in a number of regions and have major socio-economic impacts. Here we show by means of climate model integrations that El Niño events may be boosted by global warming. An important factor causing El Niño intensification is warming of the western Pacific warm pool, which strongly enhances surface zonal wind sensitivity to eastern equatorial Pacific sea surface temperature anomalies. This in conjunction with larger and more zonally asymmetric equatorial Pacific upper ocean heat content supports stronger and longer lasting El Niños. The most intense events, termed Super El Niños, drive extraordinary global teleconnections which are associated with exceptional surface air temperature and rainfall anomalies over many land areas.
KeywordsCMIP5 Model Ocean Heat Content Bjerknes Feedback Surface Zonal Wind Kiel Climate Model
This study was supported by RACE and SACUS of the BMBF and SFB 754 Climate-Biogeochemistry Interactions in the Tropical Ocean of the DFG. A partial support of Russian Ministry of Education and Science (contract 14.В25.31.0026), Russian Foundation for Basic Research (14-05-00518) and Russian Science Foundation (14-17-00700) is acknowledged. The integrations were performed at the Computing Centre of Kiel University.
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