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OMI HCHO is validated over the continental US (CONUS), and used to analyze regional sources in Northeast Asia (NA) and Southeast Asia (SA). OMI HCHO Version 2.0 data show unrealistic trends, which prompted the production of a corrected OMI HCHO data set. EOF and SVD are utilized to compare the spatial and temporal variability between OMI HCHO against GOME and SCIAMACHY, and against GEOS-Chem. CONUS HCHO chemistry is well studied; its concentrations are greatest in the southeastern US with annual cycle maximums corresponding to the summer vegetation. The corrected OMI HCHO agrees with this understanding as well as with the other sensors measurements and has no unrealistic trends. In NA the annual cycle is super-posed by extremely large concentrations in polluted mega-cities. The other sensors generally agree with NA's OMI HCHO regional distribution, but megacity signal is not seen in GEOS-Chem. Our study supports the findings proposed by others that the emission inventory used in GEOS-Chem significantly underestimates anthropogenic influence on HCHO emission over megacities. The persistent mega-city signal is also present in SA. In SA the spatial and temporal patterns of OMI HCHO show a maximum in the dry season. The patterns are in remarkably good agreement with fire counts, which illustrates that the variability of HCHO over SA is strongly influenced by biomass burning. The corrected OMI HCHO data has realistic trends, conforms to well-known sources over CONUS, and has shown a stationary large concentration over polluted Asian mega-cities, and a widespread biomass burning in SA.
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http://dx.doi.org/10.1016/j.scitotenv.2014.04.108 | DOI Listing |
Huan Jing Ke Xue
November 2024
Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China.
Based on Ozone (O) Monitoring Instrument satellite remoting sensing data and reanalysis meteorological data, an analysis was conducted on the spatiotemporal distribution and trends of tropospheric nitrogen dioxide (NO) and formaldehyde (HCHO) in Guangdong Province from 2015 to 2020. The study also examined the changing characteristics of O generation sensitivity in relation to meteorological parameters. The results indicated that during 2015-2020, the tropospheric NO column concentration in Guangdong Province exhibited a distribution pattern with the Pearl River Delta (PRD) Region as the high-value center gradually decreasing towards the surrounding areas, with the most substantial decline observed in the Pearl River Delta.
View Article and Find Full Text PDFJ Environ Sci (China)
April 2025
School of Geography and Tourism, Shaanxi Normal University, Xi' an 710000, China.
Formaldehyde (HCHO) is a high-yield product of the oxidation of volatile organic compounds (VOCs) released by anthropogenic activities, fires, and vegetations. Hence, we examined the spatiotemporal variation trends in HCHO columns observed using the Ozone Monitoring Instrument (OMI) during 2005-2021 across the Fenwei Plain (FWP) and analysed the source and variability of HCHO using multi-source data, such as thermal anomalies. The spatial distribution of the annual mean HCHO in the FWP increased from northwest to southeast during 2005-2021, and the high-value aggregation areas contracted and gradually clustered, forming a belt-shaped distribution area from Xi'an to Baoji, north of the Qinling Mountains.
View Article and Find Full Text PDFSci Total Environ
December 2024
School of Geography and Remote Sensing, Guangzhou University, Guangzhou 510006, China; Institute of Aerospace Remote Sensing Innovations, Guangzhou University, Guangzhou, Guangdong, China.
Monitoring the spatiotemporal distribution of formaldehyde (HCHO) is crucial for reducing volatile organic compounds (VOCs) emissions, and the long-term evolution of socio-natural sources contributions to tropospheric HCHO over China is still unclear. We propose an oversampling algorithm for quantitatively tracking the evolution of uncertainty, which lowers the uncertainty of the original Level 2 OMI HCHO data (50 % -105 %) to 0-50 %, and then we examine the evolution of contributions from various emissions sources applying multi-scale correlation. We found that the high formaldehyde vertical column densities (VCD) caused by human activities in eastern China are crossing the Hu Huanyong Line, which was formerly used to demarcate the population distribution.
View Article and Find Full Text PDFHuan Jing Ke Xue
August 2024
Monitoring and Assessment Center for Greenhouse Gases and Carbon Neutrality of China Meteorological Administration, Shanxi Branch, Shanxi Institute of Meteorological Science, Taiyuan 030002, China.
Satellite-based formaldehyde(HCHO)columns and tropospheric nitrogen dioxide columns were observed using the Ozone Monitoring Instrument(OMI),and groundbased observations of ozone(O)for May-August from 2013 to 2022 were connected to calculate the threshold values of the HCHO to NO ratio(FNR)in Shanxi Province. Then,the spatiotemporal distributions and variations in summertime ozone photochemical production regimes were analyzed. The results showed that:① The volatile organic compound(VOC) -sensitive regime area(FNR < 2.
View Article and Find Full Text PDFEnviron Pollut
October 2024
College of Chemistry, Chemical Engineering and Environment, Minnan Normal University, Zhangzhou, 363000, China; Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou, 363000, China; Fujian Province University Key Laboratory of Pollution Monitoring and Control, Minnan Normal University, Zhangzhou, 363000, China. Electronic address:
In the troposphere, ozone (O) formation can be limited by NOx, VOCs, or both, complicating efforts to reduce O by controlling its precursors. This study used formaldehyde (HCHO) data and nitrogen dioxide (NO) data from the Ozone Monitoring Instrument (OMI) to analyze O formation sensitivity in Fujian from 2012 to 2021. Over the past decade, an 8.
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