Evolution of ocean heat content related to ENSO
- Author(s)
- Lijing Cheng, Kevin E. Trenberth, John T. Fasullo, Michael Mayer, Magdalena Balmaseda, Jiang Zhu
- Abstract
As the strongest inter-annual perturbation to the climate system, the El Niño-Southern Oscillation (ENSO) dominates the year-to-year variability of the ocean energy budget. Here we combine ocean observations, re-analyses, and surface flux data with Earth system model simulations to obtain estimates of the different terms affecting the redistribution of energy in the Earth system during ENSO events, including exchanges between ocean and atmosphere, among different ocean basins, lateral and vertical rearrangements. This comprehensive inventory allows better understanding of the regional and global evolution of ocean heat related to ENSO, and provides observational metrics to benchmark performance of climate models. Results confirm that there is a strong negative ocean heat content tendency (OHCT) in the tropical Pacific Ocean during El Niño, mainly through enhanced air-sea heat fluxes (Q) into the atmosphere driven by high sea surface temperatures. As well as this diabatic component, there is an adiabatic redistribution of heat both laterally and vertically (0-100m and 100-300m) in the tropical Pacific and Indian oceans that dominates the local OHCT. Heat is also transported and discharged from 20oS-5oN into off-equatorial regions within 5-20oN during and after El Niño. OHCT and Q changes outside of the tropical Pacific Ocean indicates the ENSO-driven atmospheric teleconnections and changes of ocean heat transport (i.e. Indonesian Throughflow). The tropical Atlantic and Indian oceans warm during El Niño, partly offsetting the tropical Pacific cooling for the tropical oceans as a whole. While there are distinct regional OHCT changes, many compensate each other resulting in a weak but robust net global ocean cooling during and after El Niño.
- Organisation(s)
- Department of Meteorology and Geophysics
- External organisation(s)
- Chinese Academy of Sciences (CAS), National Center for Atmospheric Research (NCAR), European Centre for Medium-Range Weather Forecasts (ECMWF), University of the Chinese Academy of Sciences
- Journal
- Journal of Climate
- Volume
- 32
- Pages
- 3529-3556
- No. of pages
- 28
- ISSN
- 0894-8755
- DOI
- https://doi.org/10.1175/JCLI-D-18-0607.1
- Publication date
- 06-2019
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105204 Climatology
- Keywords
- ASJC Scopus subject areas
- Atmospheric Science
- Sustainable Development Goals
- SDG 13 - Climate Action
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/evolution-of-ocean-heat-content-related-to-enso(b1e0c5c3-4f12-462c-b964-d676f492ac9f).html