Title: | Global Significant Changes in Formaldehyde (HCHO) Columns Observed From Space at the Early Stage of the COVID-19 Pandemic |
Author(s): | Sun W; Zhu L; De Smedt I; Bai B; Pu D; Chen Y; Shu L; Wang D; Fu TM; Wang X; Yang X; |
Address: | School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen China. Division of Atmospheric Composition Royal Belgian Institute for Space Aeronomy (BIRA-IASB) Brussels Belgium. Department of Environmental Science and Engineering Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Fudan University Shanghai China |
ISSN/ISBN: | 0094-8276 (Print) 1944-8007 (Electronic) 0094-8276 (Linking) |
Abstract: | "Satellite HCHO data are widely used as a reliable proxy of non-methane volatile organic compounds (NMVOCs) to constrain underlying emissions and chemistry. Here, we examine global significant changes in HCHO columns at the early stage of the COVID-19 pandemic (January-April 2020) compared with the same period in 2019 with observations from the TROPOspheric Monitoring Instrument (TROPOMI). HCHO columns decline (11.0%) in the Northern China Plain (NCP) because of a combination of meteorological impacts, lower HCHO yields as NO (x) emission plunges (by 36.0%), and reduced NMVOC emissions (by 15.0%) resulting from the lockdown. HCHO columns change near Beijing (+8.4%) due mainly to elevated hydroxyl radical as NO (x) emission decreases in a NO (x) -saturated regime. HCHO columns change in Australia (+17.5%), Northeastern Myanmar of Southeast Asia (+14.9%), Central Africa (+7.8%), and Central America (+18.9%), consistent with fire activities. Our work also points to other changes related to temperature and meteorological variations" |
Keywords: | Covid-19 Hcho NMVOCs Tropomi; |
Notes: | "PubMed-not-MEDLINESun, Wenfu Zhu, Lei De Smedt, Isabelle Bai, Bin Pu, Dongchuan Chen, Yuyang Shu, Lei Wang, Dakang Fu, Tzung-May Wang, Xiaofei Yang, Xin eng 2021/04/01 Geophys Res Lett. 2021 Feb 28; 48(4):2e020GL091265. doi: 10.1029/2020GL091265. Epub 2021 Feb 23" |