Impact of selecting different reference spectra on errors in doas analysis

Abstract

This paper presents an analysis of various sources of errors for measurements of atmospheric trace gases concentrations, based on DOAS (Differential Optical Absorption Spectroscopy). The error analysis is based on measurements done in Galati city on 11 October 2018. The spectral window was 425-490 nm which is used for NO₂ detection in the lower atmosphere. Two sets of reference spectra were used: one recorded during a measurement campaign of the project DANS in Galati city and one recorded in May 2015 in a remote area at high altitudes, where NO₂ sources are scarce. This investigation will provide a more reliable method of reducing the errors in NO₂ DOAS spectral analysis by selecting appropriate reference spectra.