https://www.researchsquare.com/article/rs-5901920/v1
*Authors* Yang Cao, Hao Wang, Yannian Zhu, Minghuai Wang, Daniel Rosenfeld, Chen Zhou, Zhonghua Zheng, Hugh Coe, David Topping, Jihu Liu, Kang-En Huang, Yuan Liang, Haipeng Zhang, Heming Bai, Man Yue https://doi.org/10.21203/rs.3.rs-5901920/v1 *12 February 2025* *Abstract* Over the past two decades, anthropogenic emission reductions and global warming have impacted marine low clouds through aerosol-cloud interactions (ACI) and cloud feedback, yet their quantitative contributions remain unclear. This study employs a deep learning model (CNNMet−Nd) and Community Earth System Model version 2 (CESM2) to disentangle these effects. CNNMet−Nd reveals that aerosol-driven changes in cloud droplet number concentration dominate near-global marine low cloud shortwave radiative effect changes (ΔCRE), contributing 0.42 ± 0.08 Wm⁻² per 20 years, compared to 0.05 ± 0.37 Wm⁻² from cloud feedback. CESM2 effectively reproduces the predominant influence of aerosol reductions on ΔCRE by CNNMet−Nd, lending us confidence for a stronger estimate of global effective radiative forcing due to ACI (ERFaci) of -1.29 Wm⁻² since the preindustrial era. These findings highlight the critical role of ACI in shaping marine low cloud trends and its broader climate implications, especially under ongoing emission reduction efforts. *Source: ResearchSquare* -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/geoengineering/CAHJsh99pKrFd50x1s1V60%3DHCxqrhksV-NO38v8PF4AJ%2BBLHAgg%40mail.gmail.com.
