FY 2021 ENSO Diversity Capotondi, A., A.T. Wittenberg, J.-S. Kug, K. Takahashi, and M.J. McPhaden Chapter 4 in El Niño Southern Oscillation in a Changing Climate, M.J. McPhaden, A. Santoso, and W. Cai (eds.), Geophysical Monograph 253, American Geophysical Union, Wiley, 65–86, doi: 10.1002/9781119548164.ch4, View online (2020) Summary. ENSO events display large interevent differences in amplitude, spatial pattern, and temporal evolution. The differences in spatial pattern, which have important consequences for ENSO teleconnections and societal impacts, have become known as “ENSO diversity.” In this chapter we review key aspects of ENSO diversity, including ENSO's surface and subsurface characteristics, underlying dynamics, predictability, low‐frequency variations, and long‐term evolution, as well as the representation of ENSO diversity in climate models. To better understand the origin of ENSO diversity and identify specific characteristics of different event types, many different classification schemes have been proposed. Here we describe these different approaches and the insights they may provide on the nature of event‐to‐event differences. The last two decades have seen a greater number of El Niño events with the largest sea surface temperature anomalies in the central Pacific. Current research seeks to determine whether such changes in ENSO characteristics were the result of anthropogenic greenhouse gas forcing or just a manifestation of natural variability, and whether and how climate change may affect ENSO diversity in the future. Feature Publications | Outstanding Scientific Publications Contact Sandra Bigley | Help
