Measurements of column content and vertical distribution of NO2 at Zvenigorod Scientific Station

摘要

Since 1990, regular measurements of columnar abundance and vertical distribution of NO$-2$/ are carried out at Zvenigorod Scientific Station (50$DGR@N, 38$DGR@E) of the Oboukhov Institute of Atmospheric Physics with the use of visible, zenith viewing, grating spectrometer scanning in the wavelength range 435-450 nm. Measurements are done during morning and evening twilight at solar zenith angles 84$DGR - 96 $DGR@. The method of NO$-2$/ derivation is based on analysis of NO$-2$/ differential absorption taking into account ozone absorption, single molecular and aerosol scattering and the Ring effect. Vertical NO$-2$/ distribution is retrieved as a solution of reverse mathematical problem using the Chahine method. The kernel in the problem is computed taking into account photochemical processes. A NO$-2$/ vertical profile is represented by ten 5-km thick layers and a thin surface layer. Counting the surface layer as an additional layer is necessary for correct NO$-2$/ determination in conditions of the lower troposphere contaminated by nitrogen oxides. Results of eight years of NO$-2$/ measurements at Zvenigorod Station are presented. The NO$-2$/ annual variations in the stratosphere and the troposphere are analyzed; effects of interannual NO$-2$/ variability are considered as well. Also analyzed are the NO$-2$/ decrease in 1992 after the Mt. Pinatubo eruption and the following gradual recovery of the NO$-2$/ layer. Other NO$-2$/ anomalies are considered as well.