Premium
Evaluation of sulfate aerosols indirect effect in marine stratocumulus clouds using observation‐derived cloud climatology
Author(s) -
Kogan Ze.,
Kogan Yefim L.,
Lilly Douglas K.
Publication year - 1996
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/96gl01793
Subject(s) - forcing (mathematics) , aerosol , cloud albedo , sulfate aerosol , environmental science , atmospheric sciences , climatology , marine stratocumulus , shortwave , cloud forcing , northern hemisphere , sulfate , albedo (alchemy) , radiative forcing , southern hemisphere , meteorology , cloud cover , cloud computing , geology , radiative transfer , geography , chemistry , physics , art , quantum mechanics , art history , organic chemistry , performance art , computer science , operating system
The indirect shortwave effect of anthropogenic sulfate aerosol augmentation in marine stratocumulus clouds has been evaluated using global cloud climatology, sulfate aerosol data from a chemical model, and cloud albedo augmentation obtained from a large‐eddy simulation (LES) cloud model with explicit microphysics. It is found that the annually and globally (over the oceans) averaged indirect shortwave forcing is −1.1 Wm −2 with a hemispheric difference of 0.4 Wm −2 . Given the many uncertainties in the aerosol‐CCN‐cloud microstructure links, this estimate, most likely, should be considered as an upper limit of the aerosol indirect forcing. The hemispheric forcing has a strong seasonal cycle with the Northern Hemisphere (NH) forcing exceeding the Southern Hemisphere (SH) forcing during the NH spring and summer and the SH forcing prevailing during the SH spring and summer. We also estimate that the single layer St/Sc contributes most to the aerosol indirect forcing (60%) with an additional 25% from the St/Sc overlapped with Ci/Cs/Cc, and 15% from St/Sc overlapped with As/Ac.