Abstract:
Anthropogenic aerosol impacts on clouds are the most uncertain drivers of climate change. Natural experiments of aerosol-cloud interactions (ACI) – e.g. ship-track-like polluted cloud tracks downwind of industrial aerosol point sources – can help reduce these uncertainties. As natural experiments of ACI serve as analogs for controlled experiments where unperturbed and perturbed conditions are known, they allow disentangling causal relationships between aerosols and clouds from the noise of meteorological covariability. The presentation introduces natural experiments where anthropogenic aerosols serve as cloud condensation nuclei and ice nuclei downwind of industrial aerosol hot spots. For such experiments, anthropogenic aerosol perturbations on clouds are detected in satellite observations. Direct observational evidence is presented for aerosol-induced glaciation of supercooled liquid-phase clouds leading to snowfall and reduced cloud cover. Finally, it is discussed how natural experiments could be used to find observational evidence for yet uncharted aerosol impacts on clouds like the invigoration of convective clouds.
What is the Joint Oslo Seminar (JOS):
- Atmospheric and climate sciences have a stronghold in Oslo among the four institutions University of Oslo, the Meteorological Institute, CICERO and NILU.
- This joint seminar invites renowned international experts to contribute to an informal series of lectures, meant to create interaction with the Oslo atmospheric and climate science community on recent highlights and analysis in the field.
- All seminars will be held on Thursdays (12:15 pm -1pm).