Strong constraints on aerosol-cloud interactions from volcanic eruptions
The climate impact of aerosols is highly uncertain owing primarily to their poorly quantified influence on cloud properties. During 2014-15, a fissure eruption in Holuhraun (Iceland) emitted huge quantities of sulphur dioxide, resulting in significant reductions in liquid cloud droplet size. Using s...
Published in: | Nature |
---|---|
Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2017
|
Subjects: | |
Online Access: | https://research.manchester.ac.uk/en/publications/36f85b55-c7f7-4d2d-af2c-56208ecd05b4 https://doi.org/10.1038/nature22974 https://pure.manchester.ac.uk/ws/files/56250766/MAIN_TEXT_affiliation_and_aknowledgement_changes_accepted.docx |
Summary: | The climate impact of aerosols is highly uncertain owing primarily to their poorly quantified influence on cloud properties. During 2014-15, a fissure eruption in Holuhraun (Iceland) emitted huge quantities of sulphur dioxide, resulting in significant reductions in liquid cloud droplet size. Using satellite observations and detailed modelling, we estimate a global mean radiative forcing from the resulting aerosol-induced cloud brightening for the time of the eruption of around -0.2 W.m -2 . Changes in cloud amount or liquid water path are undetectable, indicating that these aerosol-cloud indirect effects are modest. It supports the idea that cloud systems are well buffered against aerosol changes as only impacts on cloud effective radius appear relevant from a climate perspective, thus providing a strong constraint on aerosol-cloud interactions. This result will reduce uncertainties in future climate projections as we are able to reject the results from climate models with an excessive liquid water path response. |
---|