Solar cosmic ray effects in atmospheric chemistry evidenced from ground-based measurements Original Research Article

Ground-based measurements of nitrogen dioxide (N02) total content and photochemical modeling have been used to investigate the response of high-latitude atmosphere to solar proton events of Ground Level Event (GLE) type. Measurements of NO2 were made at Murmansk, Kola Peninsula (corrected geomagnetic latitude: 64.8°) during and after GLE of 2 May 1998. Nitrogen dioxide was measured by zenith viewing spectrophotometer in wavelength range between 435 and 450 nm. An increase (about of 20%) in total column of N02 has been detected after 2 May 1998 GLE by this facility. Model calculations based on gas phase photochemical theory quantitatively agree with observations. These results demonstrate that information obtained from ground-based measurements is usable to study the atmospheric effects of high-energy solar protons in addition to satellite data.