Geoengineering: Whiter skies?

  title={Geoengineering: Whiter skies?},
  author={Ben Kravitz and Douglas G. MacMartin and Ken Caldeira},
  journal={Geophysical Research Letters},
One proposed side effect of geoengineering with stratospheric sulfate aerosols is sky whitening during the day and afterglows near sunset, as is seen after large volcanic eruptions. Sulfate aerosols in the stratosphere would increase diffuse light received at the surface, but with a non‐uniform spectral distribution. We use a radiative transfer model to calculate spectral irradiance for idealized size distributions of sulfate aerosols. A 2% reduction in total irradiance, approximately enough to… 

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