Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 5.414
IF5.414
IF 5-year value: 5.958
IF 5-year
5.958
CiteScore value: 9.7
CiteScore
9.7
SNIP value: 1.517
SNIP1.517
IPP value: 5.61
IPP5.61
SJR value: 2.601
SJR2.601
Scimago H <br class='widget-line-break'>index value: 191
Scimago H
index
191
h5-index value: 89
h5-index89
Preprints
https://doi.org/10.5194/acp-2019-1207
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-2019-1207
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  04 Feb 2020

04 Feb 2020

Review status
This preprint is currently under review for the journal ACP.

Climate-driven chemistry and aerosol feedbacks in CMIP6 Earth system models

Gillian Thornhill1, William Collins1, Dirk Olivié2, Alex Archibald3,4, Susanne Bauer5, Ramiro Checa-Garcia6, Stephanie Fiedler7, Gerd Folberth8, Ada Gjermundsen2, Larry Horowitz9, Jean-Francois Lamarque10, Martine Michou11, Jane Mulcahy8, Pierre Nabat11, Vaishali Naik9, Fiona M. O'Connor8, Fabien Paulot9, Michael Schulz2, Catherine E. Scott12, Roland Seferian11, Chris Smith12, Toshihiko Takemura13, Simone Tilmes10, and James Weber3 Gillian Thornhill et al.
  • 1Department of Meteorology, University of Reading, Reading, RG6 6BB, UK
  • 2Norwegian Meteorological Institute, Oslo, Norway
  • 3Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
  • 4National Centre for Atmospheric Science, UK
  • 5NASA Goddard Institute for Space Studies, 2880 Broadway
  • 6IPSL/LSCE CEA-CNRS-UVSQ-UPSaclay UMR Gif sur Yvette, France
  • 7Max-Planck-Institute for Meteorology, Hamburg, 20146, Germany
  • 8Met Office Hadley Centre, Exeter, EX1 3PB, United Kingdom
  • 9GFDL/NOAA, Princeton University, Princeton, NJ 08540-6649
  • 10National Centre for Atmospheric Research, Boulder, CO, USA
  • 11Centre National de Recherches Météorologiques, Meteo-France, Toulouse Cedex, France
  • 12School of Earth and Environment, University of Leeds, Leeds, LS2 9JT
  • 13Research Institute for Applied Mechanics, Kyushu University, Fukuoka, Japan

Abstract. Feedbacks play a fundamental role in determining the magnitude of the response of the climate system to external forcing, such as from anthropogenic emissions. The latest generation of Earth system models include aerosol and chemistry components that interact with each other and with the biosphere. These interactions introduce a complex web of feedbacks which it is important to understand and quantify.

This paper addresses the multiple pathways for aerosol and chemical feedbacks in Earth system models. This is achieved by extending previous formalisms which include CO2 concentrations as a state variable to a formalism which in principle includes the concentrations of all climate-active atmospheric constituents. This framework is demonstrated by applying it to the Earth system models participating in CMIP6 with a focus on the non-CO2 reactive gases and aerosols (methane, ozone, sulphate aerosol, organic aerosol and dust).

We find that the overall climate feedback through chemistry and aerosols is negative in the CMIP6 Earth system models due to increased negative forcing from aerosols with warmer temperatures. Through diagnosing changes in methane emissions and lifetime we find that if Earth system models were to allow methane to vary interactively, methane positive feedbacks (principally wetland methane emissions and biogenic VOC emissions) would offset much of the aerosol feedbacks.

Gillian Thornhill et al.

Interactive discussion

Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Gillian Thornhill et al.

Gillian Thornhill et al.

Viewed

Total article views: 871 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
677 183 11 871 153 13 10
  • HTML: 677
  • PDF: 183
  • XML: 11
  • Total: 871
  • Supplement: 153
  • BibTeX: 13
  • EndNote: 10
Views and downloads (calculated since 04 Feb 2020)
Cumulative views and downloads (calculated since 04 Feb 2020)

Viewed (geographical distribution)

Total article views: 785 (including HTML, PDF, and XML) Thereof 782 with geography defined and 3 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Saved

No saved metrics found.

Discussed

Latest update: 29 Sep 2020
Publications Copernicus
Download
Short summary
We find that increased temperatures affect aerosols and reactive gases, by changing natural emissions and their rates of removal from the atmosphere. Changing the composition of these species in the atmosphere affects the radiative budget of the climate system and therefore amplifies or dampens the climate response of climate models of the Earth System. This study find the largest effect is a dampening of climate change as warmer temperatures increase the emissions of cooling aerosols.
We find that increased temperatures affect aerosols and reactive gases, by changing natural...
Citation
Altmetrics