Solar proton events of October-November 2003:: Ozone depletion in the Northern Hemisphere polar winter as seen by GOMOS/Envisat -: art. no. L19107

Observations of O(3) and NO(2) made by the GOMOS instrument on board European Space Agency's Envisat satellite have been used to monitor the increase of NO(2) and depletion of ozone due to the solar proton events of October-November 2003. For the first time this phenomenon was measured in polar winter conditions by a satellite instrument. Results show NO(2) enhancement of several hundred per cent and tens of per cent ozone depletion between 36 and 60 km, an effect which lasts several months after the events. A comparison of the after-event concentrations of NO(2) and ozone reveals a strong negative correlation.