Daytime CH2O and NO2 observations from MAX-DOAS measurements in Eastern Los Angeles during the COVID-19 Pandemic
Abstract
Despite continued emission reductions in Southern California, in particular reductions in NO2 of ~30% observed by the Ozone Monitoring Instrument (OMI) during the COVID-19 pandemic, regular ozone exceedances remain a prevalent issue. To improve our understanding of ozone production during the COVID-19 lockdown period, we examine vertically resolved measurements of ozone precursors, obtained using ground-based Multiple Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) in Whittier, California, ~20 km southeast of downtown Los Angeles. Continuous measurements of CH2O, NO2, and aerosol extinction over the spring/summer of 2020 are presented. We observe a reduction of NO2 of ~20% accompanied by a ~30% reduction in observed CH2O in the Whittier area compared to observations made during the summer of 2019. Comparisons of MAX-DOAS NO2 measurements with in-situ measurements from a nearby California Air Resources Board monitoring site and tropospheric NO2 retrievals from OMI are also discussed.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMA034.0006P
- Keywords:
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- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0365 Troposphere: composition and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0368 Troposphere: constituent transport and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3355 Regional modeling;
- ATMOSPHERIC PROCESSES