PNNL

Abstract

Aerosols and clouds are key components of the marine atmosphere, impacting the Earth’s radiative budget with a net cooling effect that counterbalances greenhouse gases, yet with an uncertain amplitude. Here we report recent advances in our understanding of how the different marine aerosol sources are modulated by ocean biogeochemistry and how they, in turn, shape cloud coverage and properties. We organize these findings in successive steps from ocean biogeochemical processes to particle formation by nucleation and sea spray emissions, further growth by condensation, the potential to act as cloud condensation nuclei or ice nucleating particles, and finally, their impacts on cloud formation and life cycle. We discuss how these processes may be impacted in a changing climate and potential feedback mechanisms.