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arXiv · astro-ph/0503625

Climatic and Biogeochemical Effects of a Galactic Gamma-Ray Burst

Abstract

It is likely that one or more gamma-ray bursts within our galaxy have strongly irradiated the Earth in the last Gy. This produces significant atmospheric ionization and dissociation, resulting in ozone depletion and DNA-damaging ultraviolet solar flux reaching the surface for up to a decade. Here we show the first detailed computation of two other significant effects. Visible opacity of NO2 is sufficient to reduce solar energy at the surface up to a few percent, with the greatest effect at the poles, which may be sufficient to initiate glaciation. Rainout of dilute nitric acid is could have been important for a burst nearer than our conservative nearest burst. These results support the hypothesis that the characteristics of the late Ordovician mass extinction are consistent with GRB initiation.

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Adrian L. Melott, Brian C. Thomas, Daniel P. Hogan, Larissa M. Ejzak, Charles H. Jackman. 2005-06-27. Climatic and Biogeochemical Effects of a Galactic Gamma-Ray Burst. https://doi.org/10.1029/2005gl023073

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