资源环境科技发展态势分析平台

Aerosol-cloud interactions and their resultant forcing remains one of the largest sources of uncertainty in future climate scenarios. The effective radiative forcing due to aerosol-cloud interactions (ERFaci) is a combination of two different effects, namely how aerosols modify cloud brightness (RFaci, intrinsic) and how cloud extent reacts to aerosol (cloud adjustments CA; extrinsic). Using satellite observations of warm clouds from the NASA ATrain constellation from 2007 to 2010 along with MERRA2 Reanalysis and aerosol from the SPRINTARS model, we evaluate the ERFaci in warm, marine clouds and its components, the RFaciwarm and CA(warm), while accounting for the liquid water path and local environment. We estimate the ERFaci(warm) to be 0.32 +/- 0.16Wm(-2). The RFaci(warm) dominates the ERFaci(warm) contributing 80% (0.21 +/- 0.15Wm(-2)), while the CA(warm) enhances this cooling by 20% (0.05 +/- 0.03Wm(-2)). Both the RFaci(warm) and CA(warm) vary in magnitude and sign regionally and can lead to opposite, negating effects under certain environmental conditions. Without considering the two terms separately and without constraining cloud-environment interactions, weak regional ERFaci(warm) signals may be erroneously attributed to a damped susceptibility to aerosol.