Variability in the global energy budget and transports 1985–2017

Author(s)
Chunlei Liu, Richard P. Allan, Michael Mayer, Patrick Hyder, Damien Desbruyères, Lijing Cheng, Jianjun Xu, Yu Zhang
Abstract

The study of energy flows in the Earth system is essential for understanding current climate change. To understand how energy is accumulating and being distributed within the climate system, an updated reconstruction of energy fluxes at the top of atmosphere, surface and within the atmosphere derived from observations is presented. New satellite and ocean data are combined with an improved methodology to quantify recent variability in meridional and ocean to land heat transports since 1985. A global top of atmosphere net imbalance is found to increase from 0.10 ± 0.61 W m−2 over 1985–1999 to 0.62 ± 0.1 W m−2 over 2000–2016, and the uncertainty of ± 0.61 W m−2 is related to the Argo ocean heat content changes (± 0.1 W m−2) and an additional uncertainty applying prior to 2000 relating to homogeneity adjustments. The net top of atmosphere radiative flux imbalance is dominated by the southern hemisphere (0.36 ± 0.04 PW, about 1.41 ± 0.16 W m−2) with an even larger surface net flux into the southern hemisphere ocean (0.79 ± 0.16 PW, about 3.1 ± 0.6 W m−2) over 2006–2013. In the northern hemisphere the surface net flux is of opposite sign and directed from the ocean toward the atmosphere (0.44 ± 0.16 PW, about 1.7 ± 0.6 W m−2). The sea ice melting and freezing are accounted for in the estimation of surface heat flux into the ocean. The northward oceanic heat transports are inferred from the derived surface fluxes and estimates of ocean heat accumulation. The derived cross-equatorial oceanic heat transport of 0.50 PW is higher than most previous studies, and the derived mean meridional transport of 1.23 PW at 26° N is very close to 1.22 PW from RAPID observation. The surface flux contribution dominates the magnitude of the oceanic transport, but the integrated ocean heat storage controls the interannual variability. Poleward heat transport by the atmosphere at 30° N is found to increase after 2000 (0.17 PW decade−1). The multiannual mean (2006–2013) transport of energy by the atmosphere from ocean to land is estimated as 2.65 PW, and is closely related to the ENSO variability.

Organisation(s)
Department of Meteorology and Geophysics
External organisation(s)
European Centre for Medium-Range Weather Forecasts (ECMWF), Guangdong Ocean University, Institut français de recherche pour l'exploitation de la mer (IFREMER), University of Reading, Met Office, Chinese Academy of Sciences (CAS)
Journal
Climate Dynamics
Volume
55
Pages
3381-3396
No. of pages
16
ISSN
0930-7575
DOI
https://doi.org/10.1007/s00382-020-05451-8
Publication date
09-2020
Peer reviewed
Yes
Austrian Fields of Science 2012
105204 Climatology, 105206 Meteorology
Keywords
ASJC Scopus subject areas
Atmospheric Science
Sustainable Development Goals
SDG 13 - Climate Action
Portal url
https://ucris.univie.ac.at/portal/en/publications/variability-in-the-global-energy-budget-and-transports-19852017(64769fa0-f2a0-4eea-9ebd-d42f505cd189).html