Critical Southern Ocean climate model biases traced to atmospheric model cloud errors
- Author(s)
- Patrick Hyder, John M. Edwards, Richard P. Allan, Helene T. Hewitt, Thomas J. Bracegirdle, Jonathan M. Gregory, Richard A. Wood, Andrew J. S. Meijers, Jane Mulcahy, Paul Field, Kalli Furtado, Alejandro Bodas-Salcedo, Keith D. Williams, Dan Copsey, Simon A. Josey, Chunlei Liu, Chris D. Roberts, Claudio Sanchez, Jeff Ridley, Livia Thorpe, Steven C. Hardiman, Michael Mayer, David I. Berry, Stephen E. Belcher
- Abstract
The Southern Ocean is a pivotal component of the global climate system yet it is poorly represented in climate models, with significant biases in upper-ocean temperatures, clouds and winds. Combining Atmospheric and Coupled Model Inter-comparison Project (AMIP5/CMIP5) simulations, with observations and equilibrium heat budget theory, we show that across the CMIP5 ensemble variations in sea surface temperature biases in the 40–60°S Southern Ocean are primarily caused by AMIP5 atmospheric model net surface flux bias variations, linked to cloud-related short-wave errors. Equilibration of the biases involves local coupled sea surface temperature bias feedbacks onto the surface heat flux components. In combination with wind feedbacks, these biases adversely modify upper-ocean thermal structure. Most AMIP5 atmospheric models that exhibit small net heat flux biases appear to achieve this through compensating errors. We demonstrate that targeted developments to cloud-related parameterisations provide a route to better represent the Southern Ocean in climate models and projections.
- Organisation(s)
- Department of Meteorology and Geophysics
- External organisation(s)
- University of Reading, National Centre for Earth Observations (NCEO), British Antarctic Survey, National Centre for Atmospheric Sciences (NCAS), University of Leeds, National Oceanography Centre Southampton, Met Office
- Journal
- Nature Communications
- Volume
- 9
- No. of pages
- 17
- ISSN
- 2041-1723
- DOI
- https://doi.org/10.1038/s41467-018-05634-2
- Publication date
- 09-2018
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105206 Meteorology
- Keywords
- ASJC Scopus subject areas
- General Physics and Astronomy, General Chemistry, General Biochemistry,Genetics and Molecular Biology
- Sustainable Development Goals
- SDG 13 - Climate Action
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/2128e7bb-5fc7-4256-a881-c27ec081d7d6