Comparison of Surface Energy Fluxes from Global to Local Scale

Author(s)

Johannes Mayer, Michael Mayer, Leopold Haimberger, Chunlei Liu

Abstract

This study uses the ECMWF ERA5 reanalysis and observationally constrained top-of-the-atmosphere radiative fluxes to infer net surface energy fluxes covering 1985-2018, which can be further adjusted to match the observed mean land heat uptake. Various diagnostics are applied to provide error estimates of inferred fluxes on different spatial scales. For this purpose, adjusted as well as unadjusted inferred surface fluxes are compared with other commonly used flux products. On a regional scale, the oceanic energy budget of the North Atlantic between the RAPID array at 26.5°N and moorings located farther north (e.g., at the Greenland-Scotland Ridge) is evaluated. On the station scale, a comprehensive comparison of inferred and buoy-based fluxes is presented. Results indicate that global land and ocean averages of unadjusted inferred surface fluxes agree with the observed heat uptake to within 1 W m

^-2, while satellite-derived and model-based fluxes show large global mean biases. Furthermore, the oceanic energy budget of the North Atlantic is closed to within 2.7 (-0.2) W m

^-2for the period 2005-09 when unadjusted (adjusted) inferred surface fluxes are employed. Indirect estimates of the 2004-16 mean oceanic heat transport at 26.5°N are 1.09 PW (1.17 PW with adjusted fluxes), which agrees well with observed RAPID transports. On the station scale, inferred fluxes exhibit a mean bias of -20.1 W m

^-2when using buoy-based fluxes as reference, which confirms expectations that biases increase from global to local scales. However, buoy-based fluxes as reference are debatable, and are likely positively biased, suggesting that the station-scale bias of inferred fluxes is more likely on the order of -10 W m

^-2

Organisation(s)

Department of Meteorology and Geophysics

External organisation(s)

European Centre for Medium-Range Weather Forecasts (ECMWF), Guangdong Ocean University

Journal

Journal of Climate

Volume

Pages

4551–4569

No. of pages

ISSN

0894-8755

DOI

https://doi.org/10.1175/JCLI-D-21-0598.1

Publication date

06-2022

Peer reviewed

Yes

Austrian Fields of Science 2012

105206 Meteorology

Keywords

ASJC Scopus subject areas

Atmospheric Science

Portal url

https://ucrisportal.univie.ac.at/en/publications/965d6284-88c7-4b62-8d88-03d70bd1c406