{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:30:23Z","timestamp":1760149823833,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,15]],"date-time":"2023-09-15T00:00:00Z","timestamp":1694736000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["42075063","42075066","2021YJ0280","KHK2005"],"award-info":[{"award-number":["42075063","42075066","2021YJ0280","KHK2005"]}]},{"name":"Natural Science Foundation of Sichuan Province","award":["42075063","42075066","2021YJ0280","KHK2005"],"award-info":[{"award-number":["42075063","42075066","2021YJ0280","KHK2005"]}]},{"name":"Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control","award":["42075063","42075066","2021YJ0280","KHK2005"],"award-info":[{"award-number":["42075063","42075066","2021YJ0280","KHK2005"]}]},{"name":"333 Project of Jiangsu Province, China","award":["42075063","42075066","2021YJ0280","KHK2005"],"award-info":[{"award-number":["42075063","42075066","2021YJ0280","KHK2005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The goal of this work is to analyze how double inversion layers affect fog\u2013haze events and boundary layers over Eastern China based on unmanned aerial vehicle observations. During 10\u201312 December 2020, two successive fog\u2013haze events occurred in Eastern China. Based on the unmanned aerial vehicle (UAV), wind, temperature, relative humidity (RH), and aerosol mass concentration were monitored simultaneously in Lianyungang, China. Several observations were found after analyzing the physical fields of these data. The results show that the concentrations of air pollutants during fog events were negatively correlated with horizontal visibilities. The mass concentrations of particulate matter increased rapidly (After 08:00 BJT 11) in the fog dissipation stages (PM2.5 and PM10 increased from 97 and 150 \u03bcg\/m3 to 213 and 300 \u03bcg\/m3, respectively). Double temperature inversion significantly affected fog events, where the enhancement of the lower-level temperature inversion (where the inversion layer top height was between 150 and 300 m) corresponded to the explosive growth of fog and the dissipation of the upper-level inversion layer. (The bottom height of the inversion layer was between 350 m and 600 m) This indicates the end of fog events. Fog layer thicknesses are negatively correlated with the concentrations of air pollutants in the near-surface layer. The thickening of the inversion layer near the surface corresponds to an increase (after 05:00 BJT 11 and 03:00 BJT 12) in fog layer height. The fog event is maintained when water vapor conditions are favorable enough or when there is a deep near-surface temperature inversion but the maintenance of the near-surface temperature inversion at an intensity of above 2 \u00b0C (100 m)\u22121 mainly contributes to the durations of these two fog events. Calculations through the trajectory model reveal that the air pollutant source varied during these two events, which was the main reason for the difference in air pollutant concentrations between the two events.<\/jats:p>","DOI":"10.3390\/rs15184541","type":"journal-article","created":{"date-parts":[[2023,9,17]],"date-time":"2023-09-17T23:32:27Z","timestamp":1694993547000},"page":"4541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Double Inversion Layers Affect Fog\u2013Haze Events over Eastern China\u2014Based on Unmanned Aerial Vehicles Observation"],"prefix":"10.3390","volume":"15","author":[{"given":"Ruolan","family":"Liu","sequence":"first","affiliation":[{"name":"School of Atmospheric Sciences, Chengdu University of Information Technology, Chengdu 610225, China"},{"name":"Key Laboratory of Transportation Meteorology of China Meteorological Administration, Nanjing Joint Institute for Atmospheric Sciences, Nanjing 210041, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6716-9383","authenticated-orcid":false,"given":"Duanyang","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Transportation Meteorology of China Meteorological Administration, Nanjing Joint Institute for Atmospheric Sciences, Nanjing 210041, China"}]},{"given":"Shujie","family":"Yuan","sequence":"additional","affiliation":[{"name":"School of Atmospheric Sciences, Chengdu University of Information Technology, Chengdu 610225, China"}]},{"given":"Hong","family":"Wu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Transportation Meteorology of China Meteorological Administration, Nanjing Joint Institute for Atmospheric Sciences, Nanjing 210041, China"}]},{"given":"Fan","family":"Zu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Transportation Meteorology of China Meteorological Administration, Nanjing Joint Institute for Atmospheric Sciences, Nanjing 210041, China"}]},{"given":"Ruixiang","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Transportation Meteorology of China Meteorological Administration, Nanjing Joint Institute for Atmospheric Sciences, Nanjing 210041, China"},{"name":"Lianyungang Meteorological Bureau of Jiangsu Province, Lianyungang 222000, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1016\/j.atmosenv.2016.07.003","article-title":"Temporal and spatial variations of particulate matter and gaseous pollutants in the urban area of Tehran","volume":"141","author":"Bidokhti","year":"2016","journal-title":"Atmos. Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"118100","DOI":"10.1016\/j.atmosenv.2020.118100","article-title":"Aerosol properties, trends and classification of key types over the Middle East from satellite-derived atmospheric optical data","volume":"246","author":"Sabetghadam","year":"2021","journal-title":"Atmos. Environ."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"5159","DOI":"10.1002\/joc.7525","article-title":"Dust events in southwestern Iran: Estimation of PM10 concentration based on horizontal visibility during dust events","volume":"42","author":"Hassan","year":"2022","journal-title":"Int. J. Climatol."},{"key":"ref_4","first-page":"17963","article-title":"Influence of aerosols on the formation and development of radiation fog","volume":"9","author":"Rangognio","year":"2009","journal-title":"Atmos. Chem. Phys. Discuss."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2512138","DOI":"10.1155\/2018\/2512138","article-title":"A Persistent Fog Event Involving Heavy Pollutants in Yancheng Area of Jiangsu Province","volume":"2018","author":"Zhu","year":"2018","journal-title":"Adv. Meteorol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1016\/j.jclepro.2016.05.067","article-title":"Impacts of meteorological condition and aerosol chemical compositions on visibility impairment in Nanjing, China","volume":"131","author":"Yu","year":"2016","journal-title":"J. Clean. Prod."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e2020GL087373","DOI":"10.1029\/2020GL087373","article-title":"The stove, dome, and umbrella effects of atmospheric aerosol on the development of the planetary boundary layer in hazy regions","volume":"47","author":"Ma","year":"2020","journal-title":"Geophys. Res. Lett."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"151953","DOI":"10.1016\/j.scitotenv.2021.151953","article-title":"How do aerosols above the residual layer affect the planetary boundary layer height?","volume":"814","author":"Ma","year":"2022","journal-title":"Sci. Total Environ."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5739","DOI":"10.5194\/acp-21-5739-2021","article-title":"The impact threshold of the aerosol radiative forcing on the boundary layer structure in the pollution region","volume":"21","author":"Zhao","year":"2021","journal-title":"Atmos. Chem. Phys."},{"key":"ref_10","first-page":"863","article-title":"Analysis of Continuity of Fog, Light Fog and Haze Climate Series by Automatic Identification and Manual Observation","volume":"37","author":"Ren","year":"2018","journal-title":"Plateau Meteorol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1007\/s00376-018-8017-6","article-title":"Observational Study on the Supercooled Fog Droplet Spectrum Distribution and Icing Accumulation Mechanism in Lushan, Southeast China","volume":"36","author":"Wang","year":"2019","journal-title":"Adv. Atmos. Sci."},{"key":"ref_12","first-page":"89","article-title":"Validation of Rotorcraft UAV Boundary Layer Meteorological Observation Data and Its Application in a Heavy Fog Event in Yancheng","volume":"46","author":"Wang","year":"2020","journal-title":"Meteor. Mon."},{"key":"ref_13","first-page":"18","article-title":"Analysis of Visibility Model of PM; Pollution Based on Atmospheric Circulation","volume":"44","author":"Xu","year":"2019","journal-title":"Environ. Sci. Manag."},{"key":"ref_14","first-page":"173","article-title":"Analysis of Different-Scales Circulation Patterns and Boundary Layer Structure of PM2.5 Heavy Pollutions in Beijing during Winter","volume":"19","author":"Wang","year":"2014","journal-title":"Clim. Environ. Res."},{"key":"ref_15","first-page":"54","article-title":"Diagnostic analysis of a heavy fog event in November of 2009 in the south of Jiangsu province","volume":"27","author":"Chen","year":"2011","journal-title":"J. Meteorol. Environ."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1088","DOI":"10.1016\/j.apr.2018.04.009","article-title":"Boundary-layer features and regional transport process of an extreme haze pollution event in Nanjing, China","volume":"9","author":"Liu","year":"2018","journal-title":"Atmos. Pollut. Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1907","DOI":"10.1175\/MWR-D-14-00207.1","article-title":"Atmospheric boundary layer structure and turbulence during sea fog on the southern China coast","volume":"143","author":"Huang","year":"2015","journal-title":"Mon. Weather. Rev."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1007\/s10546-015-0076-y","article-title":"A Study of the Physical Processes of an Advection Fog Boundary Layer","volume":"158","author":"Liu","year":"2016","journal-title":"Boundary-Layer. Meteorol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1016\/j.atmosres.2014.05.027","article-title":"Vertical distribution of microphysical properties in radiation fogs\u2014A case study","volume":"151","author":"Egli","year":"2015","journal-title":"Atmos. Res."},{"key":"ref_20","first-page":"410","article-title":"Observational Study of Cloud Condensation Nuclei Properties at Various Altitudes of Huangshan Mountains","volume":"38","author":"Li","year":"2014","journal-title":"Chin. J. Atmos. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Liu, D., Liu, X., Wang, H., Li, Y., Kang, Z., Cao, L., Yu, X., and Chen, H. (2017). A New Type of Haze? The December 2015 Purple (Magenta) Haze Event in Nanjing, China. Atmosphere, 8.","DOI":"10.3390\/atmos8040076"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"31","DOI":"10.5194\/acp-17-31-2017","article-title":"Air quality improvement in a megacity: Implications from 2015 Beijing Parade Blue pollution control actions","volume":"17","author":"Xu","year":"2017","journal-title":"Atmos. Chem. Phys."},{"key":"ref_23","first-page":"440","article-title":"Characteristics of Turbulent Transfer and Its Temporal Evolution during an Advection Fog Period in North China","volume":"34","author":"Wu","year":"2010","journal-title":"Chin. J. Atmos. Sci."},{"key":"ref_24","first-page":"943","article-title":"Analysis of the Visibility Change in the Yangtze River Delta Region in Recent 30 Years","volume":"38","author":"Zhang","year":"2012","journal-title":"Meteor. Mon."},{"key":"ref_25","first-page":"660","article-title":"Analysis of visibility characteristics and connecting factors over the Yangtze River Delta Region during winter time","volume":"36","author":"Zhou","year":"2016","journal-title":"China Environ. Sci."},{"key":"ref_26","first-page":"290","article-title":"Characteristics of a regional air pollution process over the Pearl River Delta during October 2011","volume":"34","author":"Xiao","year":"2014","journal-title":"Acta Sci. Circumst."},{"key":"ref_27","first-page":"467","article-title":"Numerical Simulation and Conceptual Model Establishment of Fogs over Pearl River Estuary, China","volume":"32","author":"Zhang","year":"2016","journal-title":"J. Trop. Meteorol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1095","DOI":"10.1016\/j.scitotenv.2019.02.100","article-title":"Measurements of atmospheric aerosol vertical distribution above North China Plain using hexacopter","volume":"665","author":"Zhu","year":"2019","journal-title":"Sci. Total Environ."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"144135","DOI":"10.1016\/j.scitotenv.2020.144135","article-title":"Estimation of radiative forcing and heating rate based on vertical observation of black carbon in Nanjing, China","volume":"756","author":"Shi","year":"2021","journal-title":"Sci. Total Environ."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1360","DOI":"10.1016\/j.envpol.2018.09.081","article-title":"Determination of the vertical profile of aerosol chemical species in the microscale urban environment","volume":"243","author":"Chen","year":"2018","journal-title":"Environ. Pollut."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"105348","DOI":"10.1016\/j.atmosres.2020.105348","article-title":"An observational study of the boundary-layer entrainment and impact of aerosol radiative effect under aerosol-polluted conditions","volume":"250","author":"Liu","year":"2021","journal-title":"Atmos. Res."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"152693","DOI":"10.1016\/j.scitotenv.2021.152693","article-title":"Vertical profile of aerosol number size distribution during a haze pollution episode in Hefei, China","volume":"814","author":"Shen","year":"2022","journal-title":"Sci. Total Environ."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Chen, S., Liu, D., Kang, Z., Shi, Y., and Liu, M. (2021). Anomalous Atmospheric Circulation Associated with the Extremely Persistent Dense Fog Events over Eastern China in the Late Autumn of 2018. Atmosphere, 12.","DOI":"10.3390\/atmos12010111"},{"key":"ref_34","first-page":"243","article-title":"Analysis of the characteristics and variation of pollutant concentrations for a long-lasting fog and haze event in the Jiangsu area","volume":"39","author":"Wang","year":"2016","journal-title":"Trans. Atmos. Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"3148","DOI":"10.1021\/es051533g","article-title":"Chemical characteristics of PM2.5 and PM10 in haze-fog episodes in Beijing","volume":"40","author":"Sun","year":"2006","journal-title":"Environ. Sci. Technol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"119086","DOI":"10.1016\/j.atmosenv.2022.119086","article-title":"Particle number size distribution of PM1 and PM10 in fogs and implications on fog droplet evolutions","volume":"277","author":"Wu","year":"2022","journal-title":"Atmos. Environ."},{"key":"ref_37","first-page":"484","article-title":"Characteristics and sources of atmospheric pollutants during a fog-haze process in Huai\u2019an","volume":"37","author":"Liu","year":"2014","journal-title":"Trans. Atmos. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Cui, L.K., Song, X.Q., and Zhong, G.Q. (2021). Comparative Analysis of Three Methods for HYSPLIT Atmospheric Trajectories Clustering. Atmosphere, 12.","DOI":"10.3390\/atmos12060698"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Shin, J., Kim, D., and Noh, Y. (2022). Estimation of Aerosol Extinction Coefficient Using Camera Images and Application in Mass Extinction Efficiency Retrieval. Remote Sens., 14.","DOI":"10.3390\/rs14051224"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"7259","DOI":"10.5194\/amt-15-7259-2022","article-title":"A new method for calculating average visibility from the relationship between extinction coefficient and visibility","volume":"15","author":"Zhang","year":"2022","journal-title":"Atmos. Meas. Tech."},{"key":"ref_41","unstructured":"(2012). Ambient Air Quality Standards (Standard No. GB 3095-2012)."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"162728","DOI":"10.1016\/j.scitotenv.2023.162728","article-title":"Fog Scavenging of Particulate Matters in Air Pollution Events: Observation and Simulation in the Yangtze River Delta, China","volume":"876","author":"Qian","year":"2023","journal-title":"Sci. Total Environ."},{"key":"ref_43","first-page":"975","article-title":"Characteristics of fog layer during heavy pollution in winter in Beijing","volume":"12","author":"Tian","year":"2022","journal-title":"J. Environ. Eng. Technol."},{"key":"ref_44","first-page":"1","article-title":"The long rerm trend of haze and fog days and the surface layer transport conditions under haze weather in North China","volume":"34","author":"Wu","year":"2014","journal-title":"Acta Sci. Circumst."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/18\/4541\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:51:41Z","timestamp":1760129501000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/18\/4541"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,9,15]]},"references-count":44,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2023,9]]}},"alternative-id":["rs15184541"],"URL":"https:\/\/doi.org\/10.3390\/rs15184541","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2023,9,15]]}}}