{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T19:08:36Z","timestamp":1768590516127,"version":"3.49.0"},"reference-count":61,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,2,27]],"date-time":"2021-02-27T00:00:00Z","timestamp":1614384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key Research and Development Program of China","award":["2018YFC0213201"],"award-info":[{"award-number":["2018YFC0213201"]}]},{"name":"the National Key Research and Development Program of China","award":["2017YFC0209902"],"award-info":[{"award-number":["2017YFC0209902"]}]},{"name":"the National Key Research and Development Program of China","award":["2018YFC0213801"],"award-info":[{"award-number":["2018YFC0213801"]}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41530644"],"award-info":[{"award-number":["41530644"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41775029"],"award-info":[{"award-number":["41775029"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41975037"],"award-info":[{"award-number":["41975037"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U19A2044"],"award-info":[{"award-number":["U19A2044"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper studied the method for converting the aerosol extinction to the mass concentration of particulate matter (PM) and obtained the spatio-temporal distribution and transportation of aerosol, nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) based on multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations in Dalian (38.85\u00b0N, 121.36\u00b0E), Qingdao (36.35\u00b0N, 120.69\u00b0E), and Shanghai (31.60\u00b0N, 121.80\u00b0E) from 2019 to 2020. The PM2.5 measured by the in situ instrument and the PM2.5 simulated by the conversion formula showed a good correlation. The correlation coefficients R were 0.93 (Dalian), 0.90 (Qingdao), and 0.88 (Shanghai). A regular seasonality of the three trace gases is found, but not for aerosols. Considerable amplitudes in the weekly cycles were determined for NO2 and aerosols, but not for SO2 and HCHO. The aerosol profiles were nearly Gaussian, and the shapes of the trace gas profiles were nearly exponential, except for SO2 in Shanghai and HCHO in Qingdao. PM2.5 presented the largest transport flux, followed by NO2 and SO2. The main transport flux was the output flux from inland to sea in spring and winter. The MAX-DOAS and the Copernicus Atmosphere Monitoring Service (CAMS) models\u2019 results were compared. The overestimation of NO2 and SO2 by CAMS is due to its overestimation of near-surface gas volume mixing ratios.<\/jats:p>","DOI":"10.3390\/rs13050892","type":"journal-article","created":{"date-parts":[[2021,2,27]],"date-time":"2021-02-27T03:44:31Z","timestamp":1614397471000},"page":"892","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Variation Characteristics and Transportation of Aerosol, NO2, SO2, and HCHO in Coastal Cities of Eastern China: Dalian, Qingdao, and Shanghai"],"prefix":"10.3390","volume":"13","author":[{"given":"Xiaomei","family":"Li","sequence":"first","affiliation":[{"name":"Key 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"},{"name":"University of Science and Technology of China, Hefei 230026, China"}]},{"given":"Pinhua","family":"Xie","sequence":"additional","affiliation":[{"name":"Key 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"},{"name":"University of Science and Technology of China, Hefei 230026, China"},{"name":"CAS Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China"},{"name":"University of Chinese Academy of Sciences, Hefei 230031, China"}]},{"given":"Ang","family":"Li","sequence":"additional","affiliation":[{"name":"Key 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"}]},{"given":"Jin","family":"Xu","sequence":"additional","affiliation":[{"name":"Key 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"}]},{"given":"Zhaokun","family":"Hu","sequence":"additional","affiliation":[{"name":"Key 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"}]},{"given":"Hongmei","family":"Ren","sequence":"additional","affiliation":[{"name":"Key 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"},{"name":"University of Science and Technology of China, Hefei 230026, China"}]},{"given":"Hongyan","family":"Zhong","sequence":"additional","affiliation":[{"name":"Key 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"},{"name":"Anhui University, Hefei 230601, China"}]},{"given":"Bo","family":"Ren","sequence":"additional","affiliation":[{"name":"Key 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"},{"name":"University of Science and Technology of China, Hefei 230026, China"}]},{"given":"Xin","family":"Tian","sequence":"additional","affiliation":[{"name":"Key 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"},{"name":"Anhui University, Hefei 230601, China"}]},{"given":"Yeyuan","family":"Huang","sequence":"additional","affiliation":[{"name":"Key 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"},{"name":"University of Science and Technology of China, Hefei 230026, China"}]},{"given":"Wenxuan","family":"Chai","sequence":"additional","affiliation":[{"name":"China National Environmental Monitoring Center, Beijing 100012, China"}]},{"given":"Shuai","family":"Wang","sequence":"additional","affiliation":[{"name":"China National Environmental Monitoring Center, Beijing 100012, China"}]},{"given":"Qingbo","family":"Li","sequence":"additional","affiliation":[{"name":"Dalian Maritime University, Dalian 116026, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1126\/science.255.5043.423","article-title":"Climate forcing by anthropogenic aerosols","volume":"255","author":"Charlson","year":"1992","journal-title":"Science"},{"key":"ref_2","first-page":"6-1","article-title":"Emissions of N2O and NO from fertilized fields: Summary of available measurement data","volume":"16","author":"Bouwman","year":"2002","journal-title":"Glob. Biogeochem. Cycles"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1370","DOI":"10.1080\/15287394.2010.497440","article-title":"Acute health effects associated with exposure to volcanic air pollution (vog) from increased activity at Kilauea Volcano in 2008","volume":"73","author":"Longo","year":"2010","journal-title":"J. Toxicol. Environ. Health Part A"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"909","DOI":"10.5194\/acp-5-909-2005","article-title":"MAX-DOAS measurements of formaldehyde in the Po-Valley","volume":"5","author":"Heckel","year":"2005","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"231","DOI":"10.5194\/acp-4-231-2004","article-title":"Multi axis differential optical absorption spectroscopy (MAX-DOAS)","volume":"4","author":"Platt","year":"2004","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2035","DOI":"10.5194\/acp-17-2035-2017","article-title":"Contributions of trans-boundary transport to summertime air quality in Beijing, China","volume":"17","author":"Wu","year":"2017","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"5089","DOI":"10.5194\/amt-9-5089-2016","article-title":"MAX-DOAS retrieval of aerosol extinction properties in Madrid, Spain","volume":"9","author":"Wang","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4803","DOI":"10.5194\/amt-9-4803-2016","article-title":"Absolute calibration of the colour index and O4 absorption derived from Multi AXis (MAX-)DOAS measurements and their application to a standardised cloud classification algorithm","volume":"9","author":"Wagner","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"817706","DOI":"10.1117\/12.897941","article-title":"Atmospheric aerosol characterization combining multi-wavelength Raman lidar and MAX-DOAS meas-urements in Gwanjgu","volume":"8177","author":"Kassianov","year":"2011","journal-title":"Remote Sens. Clouds Atoms. XVI"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1029\/2004JD004904","article-title":"MAX-DOAS O4 measurements: A new technique to derive information on atmospheric aerosols-principles and information content","volume":"109","author":"Wagner","year":"2004","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"136258","DOI":"10.1016\/j.scitotenv.2019.136258","article-title":"Identifying the winter-time sources of volatile organic compounds (VOCs) from MAX-DOAS measured formaldehyde and glyoxal in Chongqing, southwest China","volume":"715","author":"Xing","year":"2020","journal-title":"Sci. Total Environ."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"765","DOI":"10.5194\/acp-14-765-2014","article-title":"Four years of ground-based MAX-DOAS observations of HONO and NO2 in the Beijing area","volume":"14","author":"Hendrick","year":"2014","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"6973","DOI":"10.5194\/acp-20-6973-2020","article-title":"MAX-DOAS measurements of NO2, SO2, HCHO, and BrO at the Mt. Waliguan WMO GAW global baseline station in the Tibetan Plateau","volume":"20","author":"Ma","year":"2020","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1016\/j.atmosres.2019.05.016","article-title":"Evolution of the vertical structure of air pollutants during winter heavy pollution episodes: The role of regional transport and poten-tial sources","volume":"228","author":"Hong","year":"2019","journal-title":"Atmos. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"31942","DOI":"10.1364\/OE.26.031942","article-title":"Dual-wavelength Mie-scattering Scheimpflug lidar system developed for the studies of the aerosol extinction coefficient and the \u00c5ngstr\u00f6m exponent","volume":"26","author":"Mei","year":"2018","journal-title":"Opt. Express"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Zhao, H., Che, H., Wang, Y., Wang, H., Ma, Y., Wang, Y., and Zhang, X. (2016). Investigation of the optical properties of aerosols over the coastal region at Dalian, Northeast China. Atmosphere, 7.","DOI":"10.3390\/atmos7080103"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"565","DOI":"10.5194\/acp-19-565-2019","article-title":"Seesaw haze pollution in North China modulated by the sub-seasonal variability of atmospheric circulation","volume":"19","author":"Zhang","year":"2019","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"125861","DOI":"10.1016\/j.chemosphere.2020.125861","article-title":"Characteristics and sources of PM2.5 with focus on two severe pollution events in a coastal city of Qingdao, China","volume":"247","author":"Gao","year":"2020","journal-title":"Chemosphere"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Wu, R., Zhou, X., Wang, L., Wang, Z., Zhou, Y., Zhang, J., and Wang, W. (2017). PM2.5 characteristics in Qingdao and across coastal cities in China. Atmosphere, 8.","DOI":"10.3390\/atmos8040077"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"117384","DOI":"10.1016\/j.atmosenv.2020.117384","article-title":"Vertical distributions of tropospheric formaldehyde, nitrogen dioxide, ozone and aerosol in south-ern China by ground-based MAX-DOAS and LIDAR measurements during PRIDE-GBA 2018 campaign","volume":"226","author":"Luo","year":"2020","journal-title":"Atmos. Environ."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"126598","DOI":"10.1016\/j.chemosphere.2020.126598","article-title":"Source assessment of atmospheric fine particulate matter in a Chinese megacity: Insights from long-term, high-time resolution chemical composition measurements from Shanghai flagship monitoring supersite","volume":"251","author":"Zhang","year":"2020","journal-title":"Chemosphere"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"14275","DOI":"10.5194\/acp-17-14275-2017","article-title":"Observations of the vertical distributions of summertime atmospheric pollutants and the corresponding ozone production in Shanghai, China","volume":"17","author":"Xing","year":"2017","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2155","DOI":"10.5194\/amt-12-2155-2019","article-title":"Intercomparison of MAX-DOAS vertical profile retrieval algorithms: Studies using synthetic data","volume":"12","author":"Beirle","year":"2019","journal-title":"Atmos. Meas. Tech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4171","DOI":"10.5194\/amt-12-4171-2019","article-title":"Full-azimuthal imaging-DOAS observations of NO2 and O4 during CINDI-2","volume":"12","author":"Peters","year":"2019","journal-title":"Atmos. Meas. Tech."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"6666","DOI":"10.1016\/j.atmosenv.2006.05.049","article-title":"Source apportionment of PAHs in atmospheric particulates of Dalian: Factor analysis with nonnegative constraints and emission inventory analysis","volume":"40","author":"Wan","year":"2006","journal-title":"Atmos. Environ."},{"key":"ref_26","unstructured":"Danckaert, T., Fayt, C., Van Roozendael, M., De Smedt, I., Letocart, V., Merlaud, A., and Pinardi, G. (2017). QDOAS Software User Manual Version 3.2, BIRA-IASB."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/S0022-4073(97)00168-4","article-title":"Measurements of the NO2 absorption cross-section from 42,000 cm\u22121 to 10,000 cm\u22121 (238\u20131000 nm) at 220 K and 294 K","volume":"59","author":"Vandaele","year":"1998","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/S1010-6030(03)00062-5","article-title":"Measurements of molecular absorption spectra with the SCIAMACHY pre-flight model: Instrument characterization and reference data for atmospheric remote-sensing in the 230\u20132380 nm region","volume":"157","author":"Bogumil","year":"2003","journal-title":"J. Photochem. Photobiol. A Chem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"15371","DOI":"10.1039\/c3cp50968k","article-title":"Temperature dependent absorption cross-sections of O2\u2013O2 collision pairs between 340 and 630 nm and at atmospherically relevant pressure","volume":"15","author":"Thalman","year":"2013","journal-title":"Phys. Chem. Chem. Phys."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"7089","DOI":"10.1029\/1999JD901074","article-title":"Temperature dependence of the absorption cross sections of formaldehyde between 223 and 323 K in the wavelength range 225-375 nm","volume":"105","author":"Meller","year":"2000","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1016\/j.jphotochem.2004.03.026","article-title":"New ultraviolet absorption cross-sections of BrO at atmospheric temperatures measured by time-windowing Fourier transform spectroscopy","volume":"168","author":"Fleischmann","year":"2004","journal-title":"J. Photochem. Photobiol. A Chem."},{"key":"ref_32","first-page":"12","article-title":"Retrieving vertical profile of aerosol extinction by multi-axis differential optical absorption spectroscopy","volume":"62","author":"Wang","year":"2013","journal-title":"Acta Phys. Sin."},{"key":"ref_33","first-page":"14","article-title":"Measuring tropospheric verti-cal distribution and vertical column density of NO2 by multi-axis differential optical absorption spectroscopy","volume":"62","author":"Wang","year":"2013","journal-title":"Acta Phys. Sin."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"3719","DOI":"10.5194\/amt-10-3719-2017","article-title":"MAX-DOAS measurements of HONO slant column densities during the MAD-CAT campaign: Inter-comparison, sensitivity studies on spectral analysis settings, and error budget","volume":"10","author":"Wang","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1611","DOI":"10.1364\/OL.389093","article-title":"Inco-herent broadband cavity enhanced absorption spectroscopy (IBBCEAS)-based strategy for direct measurement of aerosol extinction in a lidar blind zone","volume":"45","author":"Meng","year":"2020","journal-title":"Opt. Lett."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2189","DOI":"10.5194\/acp-17-2189-2017","article-title":"Ground-based MAX-DOAS observations of tropospheric aerosols, NO2, SO2 and HCHO in Wuxi, China, from 2011 to 2014","volume":"17","author":"Wang","year":"2017","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"360","DOI":"10.1016\/j.atmosenv.2017.06.022","article-title":"Observations of particle extinction, PM2.5 mass concentration profile and flux in north China based on mobile lidar technique","volume":"164","author":"Lv","year":"2017","journal-title":"Atmos. Environ."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1369","DOI":"10.5194\/amt-9-1369-2016","article-title":"Profiling the PM2.5 mass concentration vertical distribution in the boundary layer","volume":"9","author":"Tao","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1002\/andp.19083300302","article-title":"Articles on the optical characteristics of turbid tubes, especially colloidal metal solutions","volume":"25","author":"Mie","year":"1908","journal-title":"Ann. Phys."},{"key":"ref_40","first-page":"673","article-title":"Retrieval on mass concentration of urban surface suspended paticulate matter with LIDAR and satellite remotesensing","volume":"49","author":"Li","year":"2013","journal-title":"Acta Sci. Nat. Univ. Pekin."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"76","DOI":"10.1016\/j.scitotenv.2017.04.194","article-title":"Investigation of hygroscopic growth effect on aerosol scattering coefficient at a rural site in the southern North China Plain","volume":"599\u2013600","author":"Wu","year":"2017","journal-title":"Sci. Total Environ."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1016\/j.jes.2016.05.045","article-title":"Comparison of inorganic chemical compositions of at-mospheric TSP, PM10 and PM2.5 in northern and southern Chinese coastal cities","volume":"55","author":"Ma","year":"2017","journal-title":"J. Environ. Sci."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1016\/S1001-0742(09)60122-4","article-title":"Composition, source, mass closure of PM2.5 aerosols for four forests in eastern China","volume":"22","author":"Li","year":"2010","journal-title":"J. Environ. Sci."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"9531","DOI":"10.5194\/acp-19-9531-2019","article-title":"Mixing layer transport flux of particulate mat-ter in Beijing, China","volume":"19","author":"Liu","year":"2019","journal-title":"Atmos. Chem. Phys."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1999","DOI":"10.1002\/qj.3803","article-title":"The ERA5 global reanalysis","volume":"146","author":"Hersbach","year":"2020","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"eaax9800","DOI":"10.1126\/sciadv.aax9800","article-title":"Pinpointing nitrogen oxide emissions from space","volume":"5","author":"Beirle","year":"2019","journal-title":"Sci. Adv."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"5629","DOI":"10.5194\/acp-13-5629-2013","article-title":"Tropospheric NO2 vertical column densities over Beijing: Results of the first three years of ground-based MAX-DOAS measurements (2008\u20132011) and satellite validation (Volume 13, p. 1547, 2013)","volume":"13","author":"Ma","year":"2013","journal-title":"Atmos. Chem. Phys."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"12519","DOI":"10.5194\/acp-15-12519-2015","article-title":"Diurnal, seasonal and long-term variations of global formaldehyde columns inferred from combined OMI and GOME-2 observations","volume":"15","author":"Stavrakou","year":"2015","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1293","DOI":"10.1016\/j.chemosphere.2016.11.140","article-title":"Sources of formaldehyde and their contributions to photochemical O3 formation at an urban site in the Pearl River Delta, southern China","volume":"168","author":"Ling","year":"2017","journal-title":"Chemosphere."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1016\/j.jes.2018.12.012","article-title":"Tropospheric NO2 vertical column densities retrieved from ground-based MAX-DOAS measurements at Shangdianzi regional atmospheric background station in China","volume":"80","author":"Cheng","year":"2019","journal-title":"J. Environ. Sci."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"5931","DOI":"10.5194\/acp-18-5931-2018","article-title":"Ship-based MAX-DOAS measurements of tropospheric NO2, SO2, and HCHO distribution along the Yangtze River","volume":"18","author":"Hong","year":"2018","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"2795","DOI":"10.5194\/acp-20-2795-2020","article-title":"Comparison of tropospheric NO2 columns from MAX-DOAS retrievals and regional air quality model simulations","volume":"20","author":"Blechschmidt","year":"2020","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"2225","DOI":"10.5194\/acp-3-2225-2003","article-title":"Weekly cycle of NO2 by GOME measurements: A signature of anthropogenic sources","volume":"3","author":"Beirle","year":"2003","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Javed, Z., Liu, C., Khokhar, M.F., Tan, W., Liu, H., Xing, C., Ji, X., Tanvir, A., Hong, Q., and Sandhu, O. (2019). Ground-based MAX-DOAS observations of CHOCHO and HCHO in Beijing and Baoding, China. Remote Sens., 11.","DOI":"10.3390\/rs11131524"},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Xu, L., Batterman, S., Chen, F., Li, J., Zhong, X., Feng, Y., Rao, Q., and Chen, F. (2017). Spatiotemporal characteristics of PM2.5 and PM10 at urban and corresponding background sites in 23 cities in China. Sci. Total Environ., 2074\u20132084.","DOI":"10.1016\/j.scitotenv.2017.05.048"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1016\/j.atmosenv.2008.10.021","article-title":"Aircraft measurements of O3, NOx, CO, VOCs, and SO2 in the Yangtze River Delta region","volume":"43","author":"Geng","year":"2009","journal-title":"Atmos. Environ."},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Luo, L., Zhu, R.-G., Song, C.-B., Peng, J.-F., Guo, W., Liu, Y., Zheng, N., Xiao, H., and Xiao, H.-Y. (2021). Changes in nitrate accumulation mechanisms as PM2.5 levels increase on the North China Plain: A perspective from the dual isotopic compositions of nitrate. Chemosphere, 263.","DOI":"10.1016\/j.chemosphere.2020.127915"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"139555","DOI":"10.1016\/j.scitotenv.2020.139555","article-title":"How aerosol transport from the North China plain contributes to air quality in northeast China","volume":"738","author":"Zhao","year":"2020","journal-title":"Sci. Total Environ."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"3199","DOI":"10.5194\/acp-8-3199-2008","article-title":"Intercomparison between aerosol optical properties by a PREDE skyradiometer and CIMEL sunphotometer over Beijing, China","volume":"8","author":"Chen","year":"2008","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s12040-020-1366-4","article-title":"Study of mixing ratios of SO2 in a tropical rural environment in south India","volume":"129","author":"Renuka","year":"2020","journal-title":"J. Earth Syst. Sci."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"3375","DOI":"10.5194\/acp-19-3375-2019","article-title":"Ground-based MAX-DOAS observations of tropo-spheric formaldehyde VCDs and comparisons with the CAMS model at a rural site near Beijing during APEC 2014","volume":"19","author":"Tian","year":"2019","journal-title":"Atmos. Chem. Phys."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/5\/892\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:29:46Z","timestamp":1760160586000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/5\/892"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,2,27]]},"references-count":61,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["rs13050892"],"URL":"https:\/\/doi.org\/10.3390\/rs13050892","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,2,27]]}}}