Quantification of Nitrogen Dioxide and Sulfur Dioxide emissions from Bucharest using a mobile-DOAS setup

Atmospheric pollution has a well-known impact on the human life, thus observing the emissions of trace gases is an important part of monitoring the atmospheric composition. This paper aims to determine the vertical column densities (VCDs) of Nitrogen Dioxide (NO₂) and Sulfur Dioxide (SO₂). These quantities will be used to calculate emissions of these pollutants quantified using a ground based mobile remote sensing technique that relies on scattered light DOAS (Differential Optical Absorption Spectroscopy) measurements. This method will be implemented using the SWING (Small Whiskbroom Imager for atmospheric compositioN monitorinG). The instrument is designed to perform airborne measurements, but for the purpose of this paper it was adapted for ground-based use by the National Institute for Aerospace Research (INCAS) in Bucharest, Romania. The source aimed to be quantified is the city of Bucharest, specifically the total emissions generated by the traffic and industry within the city. The measurements will be performed during the Spring of 2020 between February and April. The experimental setup consists of the SWING that will be mounted on the roof of a car, which allows to perform measurements along the ring road of Bucharest. There will be presented results from several days of measurements from a total of 150 hours of driving in terms of differential slant column densities (DSCDs), vertical column densities (VCDs) and quantified emissions of NO­₂ and SO₂. This study will also be used for the fine tuning of the SWING operational parameters for use on UAV platforms in future measurement campaigns.