Table 1 Global annual mean cloud changes and top-of-the-atmosphere radiative effects

From: Observationally constrained aerosol–cloud semi-direct effects

Model CBOT CLOW CMED CHI ERF RAPADJ SDE SDESW SDELW
STANDARD
CAM4 0.33 −0.14 −0.26 −0.07 0.21 0.32 0.29 0.46 −0.17
CAM5 0.07 −0.26 −0.22 −0.12 0.18 0.29 0.30 0.40 −0.10
GFDL 0.05* −0.43 −0.21 −0.04* 0.32 0.43 0.52 0.67 −0.15
HALF
CAM4 0.21 −0.02* −0.13 −0.02* 0.08 0.14 0.14 0.22 −0.08
CAM5 0.01* −0.18 −0.14 −0.11 0.10 0.15 0.17 0.22 −0.05
GFDL 0.04 −0.28 −0.13 0.02* 0.20 0.26 0.30 0.39 −0.08
VERTUNIF
CAM4 0.10 0.25 −0.19 −0.54 −0.50 −0.39 −0.67 −0.17 −0.50
CAM5 0.09 0.21 −0.22 −0.80 −0.38 −0.27 −0.54 0.07* −0.61
GFDL 0.11 0.18 −0.20 −0.71 −0.45 −0.34 −0.41 0.21 −0.62
PDRMIP
CAM4-PDRMIP 0.40 0.11 −0.19 −0.30 0.76 −1.34 −1.05 −0.28 −0.77
CAM5-PDRMIP 0.11 0.07 −0.16 −0.31 0.30 −0.98 −1.14 −0.54 −0.60
HadGEM2-ES 0.07 0.03 −0.50 −0.42 2.91 −0.64 −1.26 0.31 −1.57
MIROC-SPRINTARS 0.10 0.05 −0.10 −0.09 0.67 −0.55 −0.41 −0.06 −0.35
  1. Responses are shown for observationally constrained fine-mode aerosol forcing without dust and sea salt (STANDARD), analogous simulations with vertically uniform aerosol atmospheric heating (VERTUNIF) and PDRMIP models. Also included are simulations with the surface reduction in solar radiation and atmospheric solar heating reduced by 50% (HALF). Cloud changes are shown for the model’s lowest level (CBOT), as well as low-level (CLOW); mid-level (CMED); and high-level (CHI). Radiative effects include the effective radiative forcing (ERF); rapid adjustments (RAPADJ) and the aerosol–cloud semi-direct effect (SDE), which is also decomposed into shortwave (SDESW) and longwave (SDELW) components. RAPADJ is calculated as ERF–IRF, where IRF is the instantaneous radiative forcing (−0.11 W m−2 for STANDARD and −0.055 W m−2 for HALF). All changes are significant at the 90% confidence level, unless denoted with an asterisk. Cloud change units are %; ERF, RAPADJ and SDE units are W m−2
  2. An asterisk denotes changes that are not significant at the 90% confidence level