Change search
ReferencesLink to record
Permanent link

Direct link
Climate feedback efficiency and synergy
Max Planck Inst Meteorol, Hamburg, Germany.
Stockholm University, Faculty of Science, Department of Meteorology .
European Ctr Medium Range Weather Forecasts, Reading, Berks, England.
DMI, Copenhagen, Denmark.
Show others and affiliations
2013 (English)In: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 41, no 9-10, 2539-2554 p.Article in journal (Refereed) Published
Abstract [en]

Earth's climate sensitivity to radiative forcing induced by a doubling of the atmospheric CO2 is determined by feedback mechanisms, including changes in atmospheric water vapor, clouds and surface albedo, that act to either amplify or dampen the response. The climate system is frequently interpreted in terms of a simple energy balance model, in which it is assumed that individual feedback mechanisms are additive and act independently. Here we test these assumptions by systematically controlling, or locking, the radiative feedbacks in a state-of-the-art climate model. The method is shown to yield a near-perfect decomposition of change into partial temperature contributions pertaining to forcing and each of the feedbacks. In the studied model water vapor feedback stands for about half the temperature change, CO2-forcing about one third, while cloud and surface albedo feedback contributions are relatively small. We find a close correspondence between forcing, feedback and partial surface temperature response for the water vapor and surface albedo feedbacks, while the cloud feedback is inefficient in inducing surface temperature change. Analysis suggests that cloud-induced warming in the upper tropical troposphere, consistent with rising convective cloud anvils in a warming climate enhances the negative lapse-rate feedback, thereby offsetting some of the warming that would otherwise be attributable to this positive cloud feedback. By subsequently combining feedback mechanisms we find a positive synergy acting between the water vapor feedback and the cloud feedback; that is, the combined cloud and water vapor feedback is greater than the sum of its parts. Negative synergies surround the surface albedo feedback, as associated cloud and water vapor changes dampen the anticipated climate change induced by retreating snow and ice. Our results highlight the importance of treating the coupling between clouds, water vapor and temperature in a deepening troposphere.

Place, publisher, year, edition, pages
Springer, 2013. Vol. 41, no 9-10, 2539-2554 p.
Keyword [en]
Climate sensitivity, Climate feedback mechanisms, Synergy
National Category
Meteorology and Atmospheric Sciences
URN: urn:nbn:se:su:diva-97028DOI: 10.1007/s00382-013-1808-7ISI: 000326244700018OAI: diva2:674257


Available from: 2013-12-03 Created: 2013-12-02 Last updated: 2013-12-03Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Graversen, Rune Grand
By organisation
Department of Meteorology
In the same journal
Climate Dynamics
Meteorology and Atmospheric Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 70 hits
ReferencesLink to record
Permanent link

Direct link