Increase in the Stratospheric NO2 Content Derived from Results of Ground-Based Observations after the October 2003 Solar Proton Event

Abstract

This paper reports on the first experimental evidence of the impact of a solar proton event on the stratospheric NO₂ content derived from ground-based spectrometric measurements at middle and high latitudes of the Northern Hemisphere. In October 2003, a solar proton event caused an increase in the NO₂ content in the upper stratosphere by 0.6 × 10¹⁵ cm^–2, which accounted for about one-third of the increase in the column NO₂ content. Solar proton events may be an essential factor for variability of the column NO₂ content in the atmosphere of the high and middle latitudes.