Time‐evolving radiative feedbacks in the historical period
Author(s)
Salvi, Pietro
Gregory, Jonathan M
Ceppi, Paulo
Type
Journal Article
Abstract
We investigate the time-dependence of radiative feedback in the historical period (since the late 19th century), by analyzing experiments using coupled atmosphere–ocean climate models with historical greenhouse gas, anthropogenic aerosol, and natural forcings, each separately. We find that radiative feedback depends on forcing agent, primarily through the effect of cloud on shortwave radiation, because the various forcings cause different changes in global-mean tropospheric stability per degree of global-mean temperature change. The large time-variation of historical feedback driven by observed sea surface temperature change alone, with no forcing agents, is also consistent with tropospheric stability change, and differs from the similarly large and significant historical time-variation of feedback that is simulated in response to all forcing agents together. We show that the latter results from the varying relative sizes of individual forcings. We highlight that volcanic forcing is especially important for understanding the time-variation, because it stimulates particularly strong feedbacks that tend to reduce effective climate sensitivity. We relate this to stability changes due to enhanced surface temperature response in the Indo-Pacific warm pool.
Date Issued
2023-10-27
Date Acceptance
2023-08-24
Citation
Journal of Geophysical Research: Atmospheres, 2023, 128 (20)
ISSN
2169-8996
Publisher
American Geophysical Union
Journal / Book Title
Journal of Geophysical Research: Atmospheres
Volume
128
Issue
20
Copyright Statement
© 2023. The Authors.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
http://dx.doi.org/10.1029/2023jd038984
Publication Status
Published
Article Number
e2023JD038984
Date Publish Online
2023-10-19