{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T04:27:49Z","timestamp":1779164869047,"version":"3.51.4"},"reference-count":56,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,24]],"date-time":"2021-04-24T00:00:00Z","timestamp":1619222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Exploring the relationship between environmental air quality (EAQ) and climatic conditions on a large scale can help better understand the main distribution characteristics and the mechanisms of EAQ in China, which is significant for the implementation of policies of joint prevention and control of regional air pollution. In this study, we used the concentrations of six conventional air pollutants, i.e., carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), fine particulate matter (PM2.5), coarse particulate matter (PM10), and ozone (O3), derived from about 1300 monitoring sites in eastern China (EC) from January 2015 to December 2018. Exploiting the grading concentration limit (GB3095-2012) of various pollutants in China, we also calculated the monthly average air quality index (AQI) in EC. The results show that, generally, the EAQ has improved in all seasons in EC from 2015 to 2018. In particular, the concentrations of conventional air pollutants, such as CO, SO2, and NO2, have been decreasing year by year. However, the concentrations of particulate matter, such as PM2.5 and PM10, have changed little, and the O3 concentration increased from 2015 to 2018. Empirical mode decomposition (EOF) was used to analyze the major patterns of AQI in EC. The first mode (EOF1) was characterized by a uniform structure in AQI over EC. These phenomena are due to the precipitation variability associated with the East Asian summer monsoon (EASM), referred to as the \u201csummer\u2013winter\u201d pattern. The second EOF mode (EOF2) showed that the AQI over EC is a north\u2013south dipole pattern, which is bound by the Qinling Mountains and Huaihe River (about 35\u00b0 N). The EOF2 is mainly caused by seasonal variations of the mixed concentration of PM2.5 and O3. Associated with EOF2, the Mongolia\u2013Siberian High influences the AQI variation over northern EC by dominating the low-level winds (10 m and 850 hPa) in autumn and winter, and precipitation affects the AQI variation over southern EC in spring and summer.<\/jats:p>","DOI":"10.3390\/ijerph18094524","type":"journal-article","created":{"date-parts":[[2021,4,24]],"date-time":"2021-04-24T21:49:20Z","timestamp":1619300960000},"page":"4524","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Spatial and Temporal Characteristics of Environmental Air Quality and Its Relationship with Seasonal Climatic Conditions in Eastern China during 2015\u20132018"],"prefix":"10.3390","volume":"18","author":[{"given":"Zhiyuan","family":"Wang","sequence":"first","affiliation":[{"name":"College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoyi","family":"Shi","sequence":"additional","affiliation":[{"name":"College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chunhua","family":"Pan","sequence":"additional","affiliation":[{"name":"College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sisi","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,24]]},"reference":[{"key":"ref_1","unstructured":"WHO (2018). 9 out of 10 people worldwide breathe polluted air, but more countries are taking action. Saudi Med. J., 39, 641\u2013643."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.atmosenv.2007.09.003","article-title":"Air pollution in mega cities in China","volume":"42","author":"Chan","year":"2008","journal-title":"Atmos. Environ."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1038\/nature15371","article-title":"The contribution of outdoor air pollution sources to premature mortality on a global scale","volume":"525","author":"Lelieveld","year":"2015","journal-title":"Nature"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1289\/ehp.1103671","article-title":"Fine particulate matter constituents and cardiopulmonary mortality in a heavily polluted Chinese city","volume":"120","author":"Cao","year":"2012","journal-title":"Environ. Health Perspect."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1007\/s11069-015-2061-7","article-title":"Assessing the possible impacts of temperature change on air quality and public health in Beijing, 2008\u20132012","volume":"84","author":"Ikram","year":"2016","journal-title":"Nat. Hazards"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"625","DOI":"10.1016\/j.envres.2017.04.026","article-title":"Air pollution characteristics and health risks in Henan Province, China","volume":"156","author":"Shen","year":"2017","journal-title":"Environ. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"067009","DOI":"10.1289\/EHP4157","article-title":"Estimated contributions of emissions controls, meteorological factors, population growth, and changes in baseline mortality to reductions in ambient PM2.5 and PM2.5-related mortality in China, 2013\u20132017","volume":"127","author":"Ding","year":"2019","journal-title":"Environ. Health Perspect."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4836","DOI":"10.1021\/acs.est.5b05576","article-title":"Economic impacts from PM2.5 pollution-related health effects in China: A provincial-level analysis","volume":"50","author":"Xie","year":"2016","journal-title":"Environ. Sci. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1038\/nature21712","article-title":"Transboundary health impacts of transported global air pollution and international trade","volume":"543","author":"Zhang","year":"2017","journal-title":"Nature"},{"key":"ref_10","unstructured":"Zhang, Q., and Crooks, R. (2012). Toward an Environmentally Sustainable Future: Country Environmental Analysis of the People\u2019s Republic of China, Asian Development Bank."},{"key":"ref_11","unstructured":"Seinfeld, J.H., and Pandis, S.N. (2016). Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, John Wiley & Sons."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"15570","DOI":"10.3390\/su71115570","article-title":"Estimating the impact of urbanization on air quality in China using spatial regression models","volume":"7","author":"Fang","year":"2015","journal-title":"Sustainability"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1443","DOI":"10.1016\/j.jclepro.2015.05.005","article-title":"The influential factors of urban PM2.5 concentrations in China: A spatial econometric analysis","volume":"112","author":"Hao","year":"2016","journal-title":"J. Clean. Prod."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"338","DOI":"10.1016\/j.atmosenv.2011.11.053","article-title":"Analysis of heavy pollution episodes in selected cities of northern China","volume":"50","author":"Ji","year":"2012","journal-title":"Atmos. Environ."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"12936","DOI":"10.1073\/pnas.1300018110","article-title":"Evidence on the impact of sustained exposure to air pollution on life expectancy from China\u2019s Huai River policy","volume":"110","author":"Chen","year":"2013","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_16","first-page":"12","article-title":"From highly polluted inland city of China to \u201cLanzhou Blue\u201d: The air-pollution characteristics","volume":"10","author":"Zhao","year":"2018","journal-title":"Sci. Cold Arid Reg."},{"key":"ref_17","first-page":"1","article-title":"Ozone Source Apportionment at Urban Area during a Typical Photochemical Pollution Episode in the Summer of 2013 in the Yangtze River Delta","volume":"36","author":"Li","year":"2015","journal-title":"Environ. Sci."},{"key":"ref_18","first-page":"35","article-title":"Ozone source apportionment (OSAT) to differentiate local regional and super-regional source contributions in the Pearl River Delta region, China","volume":"117","author":"Li","year":"2012","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"20668","DOI":"10.1038\/srep20668","article-title":"\u201cAPEC blue\u201d: Secondary aerosol reductions from emission controls in Beijing","volume":"6","author":"Sun","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/j.scitotenv.2016.11.188","article-title":"The impact of the \u201cair pollution prevention and control action plan\u201d on PM2. 5 concentrations in Jing-Jin-Ji region during 2012\u20132020","volume":"580","author":"Cai","year":"2017","journal-title":"Sci. Total Environ."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.scitotenv.2016.10.231","article-title":"Haze, public health and mitigation measures in China: A review of the current evidence for further policy response","volume":"578","author":"Gao","year":"2017","journal-title":"Sci. Total Environ."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"340","DOI":"10.1038\/ngeo2138","article-title":"Tropospheric ozone variations governed by changes in stratospheric circulation","volume":"7","author":"Neu","year":"2014","journal-title":"Nat. Geosci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1221","DOI":"10.1016\/j.scitotenv.2018.06.137","article-title":"Meteorological conditions conducive to PM 2.5 pollution in winter 2016\/2017 in the Western Yangtze River Delta, China","volume":"642","author":"Shi","year":"2018","journal-title":"Sci. Total Environ."},{"key":"ref_24","first-page":"5","article-title":"Study on theory and methodology about joint prevention and control of regional air pollution","volume":"37","author":"Wang","year":"2012","journal-title":"Environ. Sustain. Dev."},{"key":"ref_25","first-page":"5","article-title":"Study on implementation of joint prevention and control of regional air pollution mechanism in China","volume":"38","author":"Cai","year":"2013","journal-title":"Environ. Sustain. Dev."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2971","DOI":"10.5194\/acp-17-2971-2017","article-title":"Attributions of meteorological and emission factors to the 2015 winter severe haze pollution episodes in China\u2019s Jing-Jin-Ji area","volume":"17","author":"Liu","year":"2017","journal-title":"Atmos. Chem. Phys."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1038\/nclimate3249","article-title":"Weather conditions conducive to Beijing severe haze more frequent under climate change","volume":"7","author":"Cai","year":"2017","journal-title":"Nat. Clim. Chang."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Ou, Y., Zhao, W., Wang, J., Zhao, W., and Zhang, B. (2017). Characteristics of Aerosol Types in Beijing and the Associations with Air Pollution from 2004 to 2015. Remote Sens., 9.","DOI":"10.3390\/rs9090898"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1016\/j.envres.2015.04.004","article-title":"Relationships between meteorological parameters and criteria air pollutants in three megacities in China","volume":"140","author":"Zhang","year":"2015","journal-title":"Environ. Res."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"6125","DOI":"10.5194\/acp-19-6125-2019","article-title":"Dominant role of emission reduction in PM 2.5 air quality improvement in Beijing during 2013\u20132017: A model-based decomposition analysis","volume":"19","author":"Cheng","year":"2019","journal-title":"Atmos. Chem. Phys."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1016\/j.scitotenv.2015.12.039","article-title":"A case study of surface ozone source apportionment during a high con-centration episode, under frequent shifting wind conditions over the Yangtze River Delta, China","volume":"544","author":"Gao","year":"2016","journal-title":"Sci. Total Environ."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"6737","DOI":"10.1016\/j.atmosenv.2004.09.017","article-title":"Simulation of sea-land breezes and a discussion of their implications on the transport of air pollution during a multi-day ozone episode in the Pearl River Delta of China","volume":"38","author":"Ding","year":"2004","journal-title":"Atmos. Environ."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/j.rse.2015.12.008","article-title":"Spatiotemporal patterns of remotely sensed PM2.5 concentration in China from 1999 to 2011","volume":"174","author":"Peng","year":"2016","journal-title":"Remote Sens. Environ."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.envres.2015.11.004","article-title":"The association between lung cancer incidence and ambient air pollution in China: A spatiotemporal analysis","volume":"144","author":"Guo","year":"2016","journal-title":"Environ. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"645","DOI":"10.3155\/1047-3289.59.6.645","article-title":"Remote sensing of particulate pollution from space: Have we reached the promised land?","volume":"59","author":"Hoff","year":"2009","journal-title":"J. Air Waste Manag. Assoc."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1016\/j.envint.2014.08.016","article-title":"Spatial and temporal variations of six criteria air pollutants in 31 provincial capital cities in China during 2013\u20132014","volume":"73","author":"Wang","year":"2014","journal-title":"Environ. Int."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1016\/j.envint.2015.11.003","article-title":"Annual and diurnal variations of gaseous and particulate pollutants in 31 provincial capital cities based on in situ air quality monitoring data from China National Environmental Monitoring Center","volume":"86","author":"Zhao","year":"2016","journal-title":"Environ. Int."},{"key":"ref_38","first-page":"33","article-title":"Spatial pattern and distributional dynamics of urban air pollution in China\u2014an empirical study based on aqi and six sub-pollutants of 161 cities","volume":"36","author":"Liu","year":"2016","journal-title":"Econ. Geogr."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"8165","DOI":"10.5194\/acp-15-8165-2015","article-title":"Characteristics and formation mechanism of continuous hazes in China: A case study during the autumn of 2014 in the North China Plain","volume":"15","author":"Yang","year":"2015","journal-title":"Atmos. Chem. Phys."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"484","DOI":"10.1016\/j.envpol.2017.01.050","article-title":"Air pollution characteristics and their relation to meteorological conditions during 2014\u20132015 in major Chinese cities","volume":"223","author":"He","year":"2017","journal-title":"Environ. Pollut."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"5895","DOI":"10.1002\/2015JD023225","article-title":"Haze days in North China and the associated atmospheric circulations based on daily visibility data from 1960 to 2012","volume":"120","author":"Chen","year":"2015","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"4205","DOI":"10.5194\/acp-16-4205-2016","article-title":"Understanding the recent trend of haze pollution in eastern China: Roles of climate change","volume":"16","author":"Wang","year":"2016","journal-title":"Atmos. Chem. Phys."},{"key":"ref_43","first-page":"1","article-title":"Arctic Sea Ice Decline Intensified Haze Pollution in Eastern China","volume":"8","author":"Wang","year":"2015","journal-title":"Atmos. Ocean. Sci. Lett"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"1381","DOI":"10.1002\/qj.864","article-title":"Atmospheric conservation properties in ERA-Interim","volume":"137","author":"Berrisford","year":"2011","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"268","DOI":"10.1016\/j.gloplacha.2013.10.003","article-title":"Can temperature extremes in China be calculated from reanalysis?","volume":"111","author":"You","year":"2013","journal-title":"Glob. Planet. Chang."},{"key":"ref_46","first-page":"371","article-title":"The distribution characters of the stratospheric Brewer-Dobson circulation inferred from ERA-interim","volume":"58","author":"Wang","year":"2015","journal-title":"Chin. J. Geophys."},{"key":"ref_47","first-page":"271","article-title":"A comparison of atmospheric temperature over China between radiosonde observations and multiple reanalysis datasets","volume":"74","author":"Guo","year":"2016","journal-title":"Acta Meteorol. Sinica"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"481","DOI":"10.1175\/1520-0493(1982)110<0481:EOEEOF>2.0.CO;2","article-title":"Examples of extended empirical orthogonal function analyses","volume":"110","author":"Weare","year":"1982","journal-title":"Mon. Weather Rev."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"6571","DOI":"10.5194\/acp-14-6571-2014","article-title":"Emission trends and mitigation options for air pollutants in East Asia","volume":"14","author":"Wang","year":"2014","journal-title":"Atmos. Chem. Phys."},{"key":"ref_50","unstructured":"National Bureau of Statistics of China (2017). China Statistical Yearbook, China Statistics Press."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"32709","DOI":"10.1007\/s11356-018-3014-y","article-title":"Air quality improvement and health benefit of PM 2.5 reduction from the coal cap policy in the Beijing\u2013Tianjin\u2013Hebei (BTH) region, China","volume":"25","author":"Guo","year":"2018","journal-title":"Environ. Sci. Pollut. Res."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"e313","DOI":"10.1016\/S2542-5196(18)30141-4","article-title":"Health impact of China\u2019s Air Pollution Prevention and Control Action Plan: An analysis of national air quality monitoring and mortality data","volume":"2","author":"Huang","year":"2018","journal-title":"Lancet Planet. Health"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"14095","DOI":"10.5194\/acp-18-14095-2018","article-title":"Trends in China\u2019s anthropogenic emissions since 2010 as the consequence of clean air actions","volume":"18","author":"Zheng","year":"2018","journal-title":"Atmos. Chem. Phys."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1175\/1520-0493(1982)110<0699:SEITEO>2.0.CO;2","article-title":"Sampling errors in the estimation of empirical orthogonal functions","volume":"110","author":"North","year":"1982","journal-title":"Mon. Weather Rev."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1016\/j.atmosenv.2017.05.008","article-title":"Spatial and temporal variation of particulate matter and gaseous pollutants in China during 2014\u20132016","volume":"161","author":"Li","year":"2017","journal-title":"Atmos. Environ."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"4457","DOI":"10.1007\/s11356-016-8181-0","article-title":"Spatial variation of air quality index and urban driving factors linkages: Evidence from Chinese cities","volume":"24","author":"Pu","year":"2017","journal-title":"Environ. Sci. Pollut. Res."}],"container-title":["International Journal of Environmental Research and Public Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/9\/4524\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:52:19Z","timestamp":1760161939000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/9\/4524"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,4,24]]},"references-count":56,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2021,5]]}},"alternative-id":["ijerph18094524"],"URL":"https:\/\/doi.org\/10.3390\/ijerph18094524","relation":{},"ISSN":["1660-4601"],"issn-type":[{"value":"1660-4601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,4,24]]}}}