Quantifying emission fluxes of atmospheric pollutants from mobile differential optical absorption spectroscopic (DOAS) observations

Qijin Zhang; Fusheng Mou; Suwen Li; Ang Li; Xude Wang; Youwen Sun

doi:10.1016/j.saa.2022.121959

Quantifying emission fluxes of atmospheric pollutants from mobile differential optical absorption spectroscopic (DOAS) observations

Spectrochim Acta A Mol Biomol Spectrosc. 2023 Feb 5:286:121959. doi: 10.1016/j.saa.2022.121959. Epub 2022 Oct 10.

Authors

Qijin Zhang¹, Fusheng Mou¹, Suwen Li², Ang Li³, Xude Wang¹, Youwen Sun⁴

Affiliations

¹ Department of Physics and Electronic Information, Huaibei Normal University, Huaibei 235000, China.
² Department of Physics and Electronic Information, Huaibei Normal University, Huaibei 235000, China. Electronic address: swli@chnu.edu.cn.
³ Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
⁴ Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China. Electronic address: ywsun@aiofm.ac.cn.

PMID: 36252302
DOI: 10.1016/j.saa.2022.121959

Abstract

This study demonstrates a mobile passive differential optical absorption spectroscopy (DOAS) based remote sensing method for quantifying the emission fluxes of soot pollutants. First, the mobile DOAS system scans the plume emitted from urban sources. Then, the DOAS method retrieves the total columns of pollutant gases along the measurement path. Combining the longitude, latitude, and mobile speed recorded by vehicle GPS, the net emission fluxes of NO₂ and SO₂ in the measurement area are calculated by coupling with the wind field data. The NO₂ flux in the region is combined with the NO to NO₂ concentration ratio in the Copernicus Atmospheric Monitoring Service (CAMS) model to calculate NO_x net emission flux in the measurement period. We conducted the mobile DOAS measurements in the coal production area and obtained the distribution of pollutant gases along the measurement path. Meanwhile, the NO₂ concentration distribution of the city and surrounding areas were reconstructed by using TROPOMI satellite data. During the mobile measurement, the net NO₂ emission flux measured by mobile DOAS are in good agreement with satellite observations (R² = 0.66). This study verified that the flux calculation method based on mobile DOAS can be used to detect urban soot pollutant gas emissions.

Keywords: CAMS; Emission flux; Mobile DOAS; NO(2) and SO(2); TROPOMI.