GRBs might not destroy the ozone layer after all...

http://www.agu.org/pubs/crossref/200...JD009391.shtml

Ozone is produced by energetic radiation, and it is assumed that NOx
compounds (also formed by gamma radiation) tend to destroy ozone. It
appears that for small increases in intensity, this is not the case.

It is not the case at very high intensities / energies, such as in
particle accelerators.

So maybe we don't need to worry about a "month long" loss of the ozone
layer, but conversion of a good deal of the atmosphere (for a few
days) to ozone...

Better cover your 'maters!

David A. Smith