El NiÃ±o’s role in Pacific Ocean sea level rise
Many tropical Pacific island nations are struggling to adapt to gradual sea level rise stemming from warming oceans and melting ice caps. Now they may also see much more frequent extreme interannual sea level swings. The culprit is a projected behavioral change of the El NiÃ±o phenomenon and its characteristic Pacific wind response, according to recent computer modeling experiments and tide-gauge analysis by scientistsÂ Matthew WidlanskyÂ andÂ Axel TimmermannÂ at theÂ International Pacific Research Center,Â University of HawaiÊ»i at MÄnoa, and their colleague Wenju Cai atÂ Commonwealth Scientific and Industrial Research OrganisationÂ (CSIRO) in Australia.
During El NiÃ±o, warm water and high sea levels shift eastward, leaving in their wake low sea levels in the western Pacific. Scientists have already shown that this east-west seesaw is often followed six months to a year later by a similar north-south sea level seesaw with water levels dropping by up to one foot (30 cm) in the Southern Hemisphere. Such sea level drops expose shallow marine ecosystems in South Pacific Islands, causing massive coral die-offs with a foul smelling tide called taimasa (pronounced [kaiâ maâsa]) by Samoans.