We investigate the dependence of radiative feedback on the pattern of sea‐surface temperature (SST) change in 14 Atmospheric General Circulation Models (AGCMs) forced with observed variations in SST and sea‐ice over the historical record from 1871 to near‐present. We find that over 1871–1980, the Earth warmed with feedbacks largely consistent and strongly correlated with long‐term climate sensitivity feedbacks (diagnosed from corresponding atmosphere‐ocean GCM
General Circulation Model (GCM) simulations with prescribed observed sea surface temperature (SST) over the historical period show systematic global shortwave cloud radiative effect (SWCRE) variations uncorrelated with global surface temperature (known as “pattern effect”). Here, we show that a single parameter that quantifies the difference in SSTs between regions of tropical deep convection and the tropical or global average (Δconv) captures the time‐varying “pattern effect” in the simulations using the PCMDI/AMIPII SST recommended for CMIP6. In particular, a large positive trend in the 1980s–1990s in Δconvexplains the change of sign to a strongly negative SWCRE feedback since the late 1970s. In these decades, the regions of deep convection warm about +50% more than the tropical average. Such an amplification is rarely observed in forced coupled atmosphere‐ocean GCM simulations, where the amplified warming is typically about +10%. During the post 2000 global warming hiatus Δconvshows little change, and the more recent period of resumed global warming is too short to robustly detect trends. In the prescribed SST simulations, Δconvis forced by the SST difference between warmer and colder regions. An index thereof (SST
- Award ID(s):
- 1743753
- NSF-PAR ID:
- 10445903
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Atmospheres
- Volume:
- 126
- Issue:
- 4
- ISSN:
- 2169-897X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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