Aerosol Science and Engineering最新文献

{"title":"Impact Assessment of Aerosol Optical Depth on Rainfall in Indian Rural Areas","authors":"Sneha Gautam,&nbsp;Janette Elizabeth,&nbsp;Alok Sagar Gautam,&nbsp;Karan Singh,&nbsp;Pullanikkat Abhilash","doi":"10.1007/s41810-022-00134-9","DOIUrl":"10.1007/s41810-022-00134-9","url":null,"abstract":"<div><p>Aerosol significantly influences the life cycle of clouds and their formation. Many studies reported worldwide on anthropogenic aerosols and their impact on clouds and their optical properties. Atmospheric remote sensing provides the best way to estimate indirectly air quality surveillance and management in megacities of developing countries like India where many cities have elevated concentration profiles of air pollutants with inadequate coverage of spatial and temporal monitoring. The results of the study highlighted the impact on rainfall patterns due to aerosol optical depth (AOD) and fine particulate matter (PM2.5) for a total of 7 years (2015–2021) over five different Indian rural sites by using MODerate Resolution Imaging Spectroradiometer (MODIS). The AOD (550 nm) and PM2.5 were retrieved from the MODIS sensor Terra satellites and the MEERA 2 model, respectively. Also, we have analyzed in this study the relationship of AOD (550 nm) with PM2.5 and meteorological variables (temperature relative humidity and precipitation) over Indian rural sites during 2015–2021. The maximum concentration of AOD (550 nm) has been measured for Gandhi college (2.94 ± 0.44) and minimum for ARM college (0.01 ± 0.28), while the maximum concentration of PM2.5 has been measured for ARM College 296.37 (µg m⁻³) and minimum for Karunya University 0.02 (µg m⁻³). Also, the relation between AOD (550 nm) with total precipitation is measured positively for all locations except Gandhi college whereby PM2.5 associated with total precipitation is measured negatively for all locations except ARM college. Finally, the relationship between PM2.5 and AOD (550 nm) is measured positively in all selected locations except Singhad Institute. The maximum rainfall has been observed for monsoon months (June–August) and post-monsoon months (October) for all locations during the study period. The maximum total precipitation has been measured for Singhad 11,674.7 (mm) and the minimum for Karunya University 4563.41 (mm). However, the results of the study indicated that there was no direct trend observed in AOD in five different selected rural Indian sites.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50524022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Annual and Inter-annual Variability Coupled with Comparison of MODIS-AERONET Retrieved Aerosol Optical Depth over a Rural Site in the Central Indo-Gangetic Basin","authors":"S. R. Varpe,&nbsp;A. R. Kolhe,&nbsp;P. Singh,&nbsp;C. M. Mahajan,&nbsp;G. C. Kutal,&nbsp;R. S. Patil,&nbsp;P. Prasad,&nbsp;G. R. Aher","doi":"10.1007/s41810-022-00135-8","DOIUrl":"10.1007/s41810-022-00135-8","url":null,"abstract":"<div><p>The long-term (2000–2015) MODIS EOS-Terra/Aqua multi-algorithm (DT, DB and combined DTB) retrieved AOD_{550 nm} and AERONET measured AOD_{550 nm} data at Gandhi College (24.87° N, 84.19° E; 60 m amsl), a rural site in the central IGB, have been employed to assess the performance of MODIS AOD products against AERONET AOD and to examine their annual and inter-annual variability. For both MODIS Terra/Aqua sensors, the linear regression data statistics reveals that the values of slopes for MODIS Terra-EOS sensor lie in the range 1.04 ± 0.03 [DB (QA = 2,3)] to 1.11 ± 0.02 [DT (QA = (2,3)] which are slightly higher than 1. Also, similar observation is noticed for MODIS Aqua-EOS sensor for which slopes of linear regression fit span over 0.99 ± 0.03 [DB (QA = 2,3)] – 1.16 ± 0.03 [DT (QA = 3)]. The intercept, however, approach zero values for both MODIS Terra/AQUA–EOS sensor at DT (QA = 3), DT (QA = 2,3), DB (QA = 2,3) and DTB combined retrieval algorithms. The evaluation/performance analysis, therefore, exhibits the observed near-perfect match of MODIS Terra/Aqua-EOS sensors derived AOD_550nm from all algorithms with AERONET measured AOD_{550 nm} as a result of magnitudes of the slope and intercept of the linear regression fit to the scatter diagrams of MODIS AOD₅₅₀ nm against AERONET AOD_{550 nm}. Results, thus indicate that at Gandhi College, the DT, and DTB combined retrieval algorithms satisfactorily estimate AOD products which can then be used to build aerosol climatology over Gandhi College. The MODIS and AERONET derived AOD_{550 nm} values over the Gandhi College indicate a distinct annual pattern with maximum AOD_{550 nm} during the winter season and minimum AOD_{550 nm} during monsoon season and winter-summer transition period. Analysis revealed that the aerosol loading starts building up over the study region from March to June of the pre-monsoon season mainly due to the high convective activity and long-range mineral dust transport from western arid regions. An increase in AOD values during the post-monsoon and winter season is primarily due to the influx of aerosols from biomass burning processes and stable atmospheric conditions, the MODIS Terra retrieved AOD_{550 nm} using DT and combined DTB algorithm showed higher values in the month of July of monsoon season as compared to MODIS Aqua retrieved AOD_{550 nm}. The inter-annual AOD trend analysis reveals that for MODIS Terra satellite there exits an increasing AOD trend during post-monsoon and winter seasons for DT (0.0233 year^–1), DB (0.0239 year^–1) and DTB (0.0246 year^–1), retrieval algorithms. For MODIS Aqua satellite also, there exists an increasing AOD_{550 nm} trend with differing but higher AOD year^–1 trend value. On the contrary, for monsoon and pre-monsoon seasons, for MODIS Terra and Aqua satellite, the AOD trends are found to be s","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s41810-022-00135-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50049148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric Aerosols: Some Highlights and Highlighters, Past to Recent Years","authors":"Zainab Mushtaq,&nbsp;Manish Sharma,&nbsp;Pargin Bangotra,&nbsp;Alok Sagar Gautam,&nbsp;Sneha Gautam","doi":"10.1007/s41810-022-00133-w","DOIUrl":"10.1007/s41810-022-00133-w","url":null,"abstract":"<div><p>The severe harmful impact of atmospheric aerosols over the environment leads to create the diverse human interests and concerns. Various progressive steps were taken by researchers and scientists to understand the fundamentals, such as nucleation and growth mechanisms, formalization of particle dynamics, characterization of the mechanisms for the particle-size dispensation, detection of chemical processes for atmospheric particle sources. The increase in population growth and different manmade activities have led to change in the environmental conditions causes to pollute the distinct vicinities. Different changes in the environment such as land use pattern, increased concentration of various greenhouse gases, and Industrial pollutants change the energy balance in our climatic conditions and affect the radiation budget of earth’ atmosphere. Such changes in climate and polluted environment leads to many health-related ailments to mankind. The present study outlines the recent research perspectives of atmospheric aerosols, their estimation through different modes, effects, and an overview of the current situations that need to be addressed before they become completely incorporated.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50102425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"UV Erythemal Radiation and Its Sensitivity to Changes in Total Column Ozone and Aerosols","authors":"Ganesh Kutal,&nbsp;Amol Kolhe,&nbsp;Sandeep Varpe,&nbsp;Chandrashekhar Mahajan,&nbsp;Prayagraj Singh,&nbsp;Gajanan Aher","doi":"10.1007/s41810-022-00132-x","DOIUrl":"10.1007/s41810-022-00132-x","url":null,"abstract":"<div><p>Ultraviolet erythemal radiation (UVER) measurements made at the Nowrosjee Wadia College (NWC) campus, Pune (India) were analysed to investigate temporal variability of UVER, to quantify effects of total column ozone (TCO) and aerosols on surface reaching UVER and to inter-compare ground-based and satellite retrieved UVER data. Diurnal variability in UVER exhibits a significant change with respect to local noon time followed by a month-to-month cyclical trend. The rate of ascent/descent of UVER during morning/evening time in winter is seen to be 0.43 minimum erythemal dose per hour (MED/hr) while during pre-monsoon season it is 0.63 MED/hr. Overall, the average value of the UVER for study period comes out to be 2.93 ± 0.8 MED/hr which is ~ 1.5 times higher than the threshold limit at which the Indian skin gets affected. There exists a quasi-anti-phase relationship between UVER and aerosol/TCO data pairs highlighting their influence on surface reaching UVER. Analysis reveals an inverse relationship between UV index (UV-I) (hence UVER) and aerosol index (AI) yielding Pearson correlation coefficient (<i>r</i>) in the range − 0.21 to − 0.88 for the period 2012–2013 and 2014–2015. The study further elucidates that the observed overall rate of decrement in UVER as a function of TCO is found to be 2.8 ± 1.5%. The Ozone Monitoring Instrument (OMI) retrieved UVER overestimates the UV-Biometer measured UVER by about 30%. The reason for overestimations being the non-inclusion of absorbing aerosols in the UVER retrieval algorithm employed in OMI estimations as well as prevalent atmospheric conditions.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50505891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and Application of Photoionization Technology for Organic Analysis of Particulate Matter","authors":"Mengna Yuan,&nbsp;Junji Cao","doi":"10.1007/s41810-022-00130-z","DOIUrl":"10.1007/s41810-022-00130-z","url":null,"abstract":"<div><p>Photoionization (PI) is a soft ionization method that does not cause the production of molecular fragments from target materials. Applications of soft photoionization–mass spectrometric methods to molecular analysis are reviewed here. A non-selective photoionization technique (single-photon ionization, SPI) can be used to measure volatile compounds with molecular mass &lt; 120 m/z, while a soft and selective technique (resonance enhanced multi-photon ionization, REMPI) is better suited for aromatic compounds whose molecular mass is &gt; 100 m/z. The development of hyphenated thermal–optical analyzer photo-ionization time-of-flight mass spectrometers (PI-TOFMS) combined with REMPI and SPI methods has enabled the analyses of evolved gaseous species, and these advanced methods have led to new insights into the elemental and organic carbon in particulate matter. Nonetheless, technical developments in the REMPI/SPI–TOFMS framework are far from complete, and there are opportunities for the development of new process analysis applications.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50077987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding the Sources of Heavy Metal Pollution in Ambient Air of Neighboring a Solid Waste Landfill Site","authors":"Umangi H. Mehta,&nbsp;Daya S. Kaul,&nbsp;Dane Westerdahl,&nbsp;Zhi Ning,&nbsp;Kai Zhang,&nbsp;Li Sun,&nbsp;Peng Wei,&nbsp;Hardik H. Gajjar,&nbsp;Jai D. Jeyaraman,&nbsp;Mansi V. Patel,&nbsp;Rutu R. Joshi","doi":"10.1007/s41810-022-00131-y","DOIUrl":"10.1007/s41810-022-00131-y","url":null,"abstract":"<p>With growing urbanization and industrialization, problems such as poor disposal practices of solid waste and ensuing uncontrolled air pollution adjacent to landfill pose threats to human and environmental wellbeing. Ahmedabad is highly polluted urban city in India and unregulated burning of solid waste further aggravates already appalling situation caused by a large number of industries and vehicle fleets. The present work was carried out to understand sources of metals in ambient air surrounding a municipal landfill known as Pirana. For the study, surrounding area of the landfill was divided into 100 rectangular cells covering almost 5 km distance from its outer boundary. A location representing major land-use feature of each cell was classified. Sampling was carried out at these locations. A total of 100 PM_5.0 samples were collected. Sampling was conducted for 3 h at each sampling location with samples collected on quartz filter paper. Measurements were performed over approximately 6 months from August to February, 2018. The filters were analyzed for metals using an Atomic Absorption Spectrometer. These measurements were used to identify pollution sources using positive matrix factorization technique and locate the hotspots of emission sources of heavy metals pollution<b>.</b> Five major sources namely, ferrous industry, nonferrous industry, vehicular emissions, re-suspended dust and solid waste burning/industrial coal combustion were identified and quantified. The average contributions of these sources to heavy metals were 20.7 ± 16.2, 18.4 ± 14.3, 19.9 ± 13.6, 21.4 ± 17.6, and 19.6 ± 10.6%, respectively. The average contribution from solid waste and industrial coal combustion is only 19.6% against the total from the combined remaining sources (~ 80.4), which means contribution from former will be lesser. Thus, solid waste burning is minor contributor for degradation of air quality; presence of many other sources around the site is actually the dominant cause of pollution.</p>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50029122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"YouTube as a Source of Information About Air Pollution","authors":"Erhan Kaya,&nbsp;Musa Şahin","doi":"10.1007/s41810-022-00129-6","DOIUrl":"10.1007/s41810-022-00129-6","url":null,"abstract":"<div><p>YouTube is an important source of information on air pollution. The information presented on youtube may be of high or low quality. In our study, we aimed to evaluate the YouTube videos for their qualities and compare their view numbers, likes, and comment numbers according to high- and low-quality groups. In our study, 32.2% of all videos were in the high-quality group, 15.1% in the intermediate quality group, and 52.7% in the low-quality group according to Global Quality Scale (GQS). Significant differences were found among the quality groups in video length (<i>p</i> &lt; 0.001), dislikes/day (<i>p</i> = 0.043), comment/day (<i>p</i> = 0.005), DISCERN (DS) tool scores (<i>p</i> &lt; 0.001). The duration and DS tool scores were higher in high-quality videos; dislikes/day and comment/day averages were higher in low-quality videos. On the other hand, there was no significant difference in views, views/day, likes/day, likes ratios among quality groups. On this important matter, low-quality videos are abundant. Considering that there are lots of nonreliable information on YouTube, it is needed that individuals should be referred to reliable videos on air pollution.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50486867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Seasonal and Meteorological Variability of Air Pollution in Singrauli Coalfield","authors":"Akhilesh Kumar Yadav,&nbsp;Saba Shirin,&nbsp;Christina Emmanouil,&nbsp;Aarif Jamal","doi":"10.1007/s41810-021-00124-3","DOIUrl":"10.1007/s41810-021-00124-3","url":null,"abstract":"<div><p>Singrauli coalfield is an intensely industrialized area in India, where coal mining takes place. The air quality parameters of particulate matter (PM) ≤ 2.5 µm, ≤ 10 µm, total suspended particles (TSP) (≤ 100 µm), NO₂ and SO₂ at mining and residential sites in this area have been monitored for 2 consecutive years (2016 and 2017). Concentration of particulate matter of both sizes (≤ 2.5 µm, ≤ 10 µm) was high at all sites and this is due to sources such as mining activities, incineration, and traffic. For all monitored air pollutants higher values were recorded in winter season than in summer and the rainy season. It is possible that meteorological factors such as wind speed and rainfall reduced ambient air pollution. Vertical variation of pollutants was recorded in the Dudhichua industrial–residential area. Higher ground level values for PM₁₀, TSP and NO₂ were recorded as it has also been noted in other high traffic areas. In general, the observed air quality parameters concentrations were slightly above the National Ambient Air Quality Standards of India. These results highlight the degraded air status in areas hosting both active coalfields and coal-burning facilities and as such the need for pollution abatement measures.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s41810-021-00124-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50431141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deposition Modeling of Airborne Particulate Matter on Human Respiratory Tract During Winter Seasons in Arid-Urban Environment","authors":"Patrick Amoatey,&nbsp;Hamid Omidvarborna,&nbsp;Khalifa Al-Jabri,&nbsp;Issa Al-Harthy,&nbsp;Mahad Said Baawain,&nbsp;Abdullah Al-Mamun","doi":"10.1007/s41810-021-00125-2","DOIUrl":"10.1007/s41810-021-00125-2","url":null,"abstract":"<div><p>This study aimed to predict winter season street-level ambient particulate matter (PM) depositions within human airways using Multiple-Path Particle Dosimetry (MPPD) model. The PM exposure concentrations in the downtown street of As-Seeb, Oman were measured continuously over 20 days (31 October–9 December 2018) using a mobile ambient air quality monitoring instrument equipped with sensors. The MPPD model together with the associated default respiratory parameters was implemented to quantify the total, head, tracheobronchial (TB), and pulmonary (PL) regional PM depositions in airways among children (3, 8, and 14 years old) and adults (18 and 21 years old) groups. The street-level PM exposure concentration (µg/m³) levels for PM₁₀ (avg 69.64; IQR 15.1), PM_2.5 (avg 13.76; IQR 1.36) and PM₁ (avg 3.67; IQR 0.52) was obtained during the winter season. The average 24-H PM_2.5 (14 µg/m3) concentration was about 60, 50 and 44% lower when compared to US National Ambient Air Quality Standards (NAAQS), Canadian Ambient Air Quality Standard (CAAQS), and WHO daily ceilings of 35, 28 and 25 µg/m³, respectively. Across all the age groups, the total airways deposition was found to be very high in PM₁₀ (92–99%), followed by PM_2.5 (61–76%) and PM₁ (33–49%) being the least. Similarly, the average deposition of PM₁₀ in the head region (76%) was observed to be more than 4–15 times higher than TB (16%) and PL (4%) for all ages. Children recorded higher PM_2.5 depositions in the TB (53–59%) region compared to adults (TB 47–51%). The PM₁₀ lobar deposition of 8-year-old children is more than 7 times higher compared to 21-year-old adults due to their lower breathing heights and higher breathing rates. In general, PM clearance was very high in TB and poor in the alveolar region.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s41810-021-00125-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50050141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aerosol–Cloud Interaction over South-Central India and Adjoining Coastal Areas","authors":"S. R. Varpe,&nbsp;C. M. Mahajan,&nbsp;A. R. Kolhe,&nbsp;G. C. Kutal,&nbsp;K. B. Budhavant,&nbsp;P. R. Singh,&nbsp;G. R. Aher","doi":"10.1007/s41810-021-00123-4","DOIUrl":"10.1007/s41810-021-00123-4","url":null,"abstract":"<div><p>The MODerate Resolution Imaging Spectroradiometer (MODIS) retrieved (2009–2015) aerosol and cloud products over South-Central India, including adjoining coastal areas, were quantitatively analyzed to explore aerosol–cloud interaction and to estimate aerosol indirect effect (AIE). The spatial distribution of aerosol optical depth (AOD) showed high AOD_{550 nm} (~ 0.7) over the northern India and is attributed to the long- and short-range transport of desert dust aerosols, dense population, and industrialization. The mean seasonal AOD_{550 nm} over region decreases from (0.55 ± 0.11) to (0.45 ± 0.05) and to (0.39 ± 0.04) for monsoon, post-monsoon, and winter seasons, respectively. The western Indian regions, particularly Pune and Jaipur, showed higher mean AOD_{500 nm} as compared to other cities. The positive correlation of aerosol indirect effect (AIE) with AOD for Pune and Pondicherry through pre- as well post- monsoon seasons for all cities except Pondicherry is ascribed to hygroscopic aerosol particulate growth. The aerosol size spectra undergo significant transformation from dominant high accumulation-mode during September–February months [with Angström exponent (AE) &gt; 1.0] to dominant augmented coarse-mode (AE &lt; 1.0) through March to June–July period. The AOD_{500 nm}-to-cloud fraction (CF) correlation coefficients range between 0.05 and 0.46 for coastal region, while for Jaipur, Pune, and overall study region, the CFs are 0.53, 0.65, and 0.75, respectively. The pre-monsoon months recorded lower (0.4–0.6 µm) cloud effective radii values than monsoon season (0.8–1.3 µm). The AOD-to-cloud liquid water path correlations for Goa and Pune (0.30–0.48) are higher than other cities (0.01–0.19). The AIE average values for metropolitan, semi-arid, coastal, high-altitude sites, and overall study region were found to be − 0.168, − 0.025, − 0.104, − 0.101, and − 0.128, respectively. There occurs a noticeable negative AIE for three categories (viz., Metropolitan, coastal, and high-altitude station), while for semi-arid category, there exists a prominent Twomey (positive AIE) effect.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50102027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}