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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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El Nino Diversity and Beyond
Each El Nino is different, in equatorial sea surface temperature (SST) and teleconnection. El Nino/the Southern Oscillation (ENSO) is often conceptually modeled as a coupled oscillation between central Pacific (Nino4) wind and eastern Pacific SST (Nino3.4) variability. Using satellite observations and ocean model experiments, we show that atmospheric convection and wind variability within the Nino3 region holds the key to El Nino diversity.
Historically the term of El Nino evolved from referring to a local coastal warming off Peru to a Pacific-wide phenomenon of global influence. In March 2017, a major coastal El Nino took place off Peru while much of the equatorial Pacific was in a La Nina state. Likewise on the other side the Pacific, a record Indian Ocean dipole took place in September 2019 while Nino3 SST was close to normal. These are some recent examples of extreme events that deviate markedly from canonical ENSO behavior. Understanding the physical causes of such extreme events is crucial to improving climate prediction.