SO2 Emission Estimates Using OMI SO2 Retrievals for 2005–2017. Issue 14 (31st July 2019)

• Record Type: Journal Article
• Authors: Qu, Zhen; Henze, Daven K.; Li, Can; Theys, Nicolas; Wang, Yi; Wang, Jun; Wang, Wei; Han, Jihyun; Shim, Changsub; Dickerson, Russell R.; Ren, Xinrong
• Is Part Of: Journal of geophysical research. Volume 124:Issue 14(2019)
• Page Start: 8336
• Page End: 8359
• Publication Date: 2019-07-31
• Subjects: top‐down SO2 emission -- satellite observation -- inverse modeling -- mass balance -- 4D‐Var -- data assimilation; Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2019JD030243
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: SO2 column densities from Ozone Monitoring Instrument provide important information on emission trends and missing sources, but there are discrepancies between different retrieval products. We employ three Ozone Monitoring Instrument SO2 retrieval products (National Aeronautics and Space Administration (NASA) standard (SP), NASA prototype, and BIRA) to study the magnitude and trend of SO2 emissions. SO2 column densities from these retrievals are most consistent when viewing angles and solar zenith angles are small, suggesting more robust emission estimates in summer and at low latitudes. We then apply a hybrid 4D‐Var/mass balance emission inversion to derive monthly SO2 emissions from the NASA SP and BIRA products. Compared to HTAPv2 emissions in 2010, both posterior emission estimates are lower in United States, India, and Southeast China, but show different changes of emissions in North China Plain. The discrepancies between monthly NASA and BIRA posterior emissions in 2010 are less than or equal to 17% in China and 34% in India. SO2 emissions increase from 2005 to 2016 by 35% (NASA)–48% (BIRA) in India, but decrease in China by 23% (NASA)–33% (BIRA) since 2008. Compared to in situ measurements, the posterior GEOS‐Chem surface SO2 concentrations have reduced NMB in China, the United States, and India but not in South Korea in 2010. BIRA posteriors have better consistency with the annual growth rate of surface SO2 measurement in China and spatial variability of SO2 concentration in China, South Korea, and India, whereas NASA SP posteriors have better seasonality. These evaluations demonstrate the capability to recover SO2 emissions using Ozone Monitoring Instrument observations. Key Points: SO2 retrievals are most consistent when VZA and SZA are small; treatment of cloud and radiative transfer can cause differences up to 4 DU Top‐down SO2 emissions are more robust between NASA and BIRA retrievals in China and India where SO2 concentrations are high SO2 emissions continuously increase in India from 2005 to 2017 but start to decrease in China from 2008