Ozone loss due to high energetic solar protons

High energetic solar protons from solar flares and coronal mass ejections affect the chemical composition of the Earth's atmosphere in the stratospheric and mesospheric altitude regions by ionization, formation of NO_x and HO_x, and, subsequently, ozone destruction. The left figure shows MIPAS observations of ozone loss (in terms of percentage ozone change relative to 26 Oct 2003) during and after the solar proton events from 28 Oct to 5 Nov 2003 over the Northern polar cap (70N - 90N). Initial ozone loss in the mesosphere reaches 70%, mainly due to HO_x formation, while longer-term (several days to weeks) ozone loss in the stratosphere is caused by NO_x formation and reaches up to 40%. The right figure shows the ozone loss as modelled by ECHAM5/MESSy which has been extended by a module parameterizing the effects of particle precipitation.

For further details see: http://www.atmos-chem-phys.net/10/7285/2010/acp-10-7285-2010.html