Journal of Atmospheric Chemistry最新文献

{"title":"Optical properties of atmospheric particles over an urban site in Mexico City and a peri-urban site in Queretaro","authors":"Rafael N. Liñán-Abanto,&nbsp;O. Peralta,&nbsp;D. Salcedo,&nbsp;L. G. Ruiz-Suárez,&nbsp;P. Arnott,&nbsp;G. Paredes-Miranda,&nbsp;H. Alvarez-Ospina,&nbsp;T. Castro","doi":"10.1007/s10874-019-09394-1","DOIUrl":"https://doi.org/10.1007/s10874-019-09394-1","url":null,"abstract":"<p>Optical properties of atmospheric particles at Mexico City (UNAM) and Queretaro (JQRO) were measured with a Photoacoustic Extinctiometer (PAX) at 870?nm. The Mexico City Metropolitan Area has around 21 million inhabitants and Queretaro Metropolitan Area has little more than a million. Observations of meteorological parameters (relative humidity, solar radiation, and wind speed) were used to identify the rainy and dry seasons and explain the daily and seasonal behaviors of particles optical properties. The measurements were made from November 1, 2014 to July 31, 2016. At UNAM, the mean values of the scattering coefficient (B_scat) in cold dry, warm dry, and rainy seasons were 35.8, 27.1, and 31.3?Mm^?1, respectively; while at JQRO were 10.9, 11.9, and 15.0?Mm^?1. The average values of the absorption coefficient (B_abs) at UNAM during the cold dry, warm dry, and rainy seasons were 14.5, 12.7, and 12.7?Mm^?1, respectively; whereas at JQRO were 4.9, 4.7, and 3.9?Mm^?1. Both absorption and scattering coefficients showed similar diurnal behaviors, but at UNAM they are three times higher than JQRO. Concentrations of criteria gases (O₃, NO, NO₂ and NO_x) were also measured. At UNAM no difference was observed between the seasonal values for the single scattering albedo (SSA); while in JQRO, the rainy season had the highest seasonal value, being 13% higher than in the dry seasons. The Mass Scattering Cross-Section (MSC) values at UNAM were close to 2 m²/g; on the other hand, at JQRO the MSC values were lower than 1 m²/g. The results suggest a seasonal variability in the aerosol optical properties in both sites, which should be verified with more long-term studies.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 3","pages":"201 - 228"},"PeriodicalIF":2.0,"publicationDate":"2019-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09394-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4069122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical characteristics and source apportionment of PM2.5 in Wuhan, China","authors":"Fan Huang,&nbsp;Jiabin Zhou,&nbsp;Nan Chen,&nbsp;Yuhua Li,&nbsp;Kuan Li,&nbsp;Shuiping Wu","doi":"10.1007/s10874-019-09395-0","DOIUrl":"https://doi.org/10.1007/s10874-019-09395-0","url":null,"abstract":"<p>Continuous online measurements of fine particulate matter mass (PM_2.5) and its chemical composition were carried out at an urban monitoring site in Wuhan from March 2017 to February 2018. The PM_2.5 mass concentration ranged from 6.3 to 223?μg/m³, with the highest in winter and the lowest in summer. Water soluble ions (WSIs) were the most abundant component in PM_2.5 (28.8?±?22.9?μg/m³), followed by carbonaceous aerosol (11.9?±?10.4?μg/m³) and elements (5.5?±?6.7?μg/m³). It is noteworthy that six episodes of sustained high PM were observed during the study period. Five major contributors of PM_2.5 were identified by positive matrix factorization (PMF) to be the iron and steel industry, fugitive dust, secondary photochemistry, traffic-related emission and biomass burning, contributing 26.3%, 5.5%, 29.5%, 29.2% and 9.6% to PM_2.5, respectively. Furthermore, conditional probability function (CPF), trajectory analysis and potential source contribution function (PSCF) were used to identify the influences of local activities and regional source. Local sources mainly include Wuhan iron and steel group, construction sites and urban trunk roads, etc. Three pollution transport pathways of PM_2.5 in Wuhan were identified to be northwest, east and south pathway, with the relative contribution of 40%, 17% and 43%, respectively. Western Henan, northern Shaanxi and southwestern Shanxi were identified to be the major potential source regions of PM_2.5 in Wuhan.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 3","pages":"245 - 262"},"PeriodicalIF":2.0,"publicationDate":"2019-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09395-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4016821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water-soluble ions and oxygen isotope in precipitation over a site in northeastern Tibetan Plateau, China","authors":"Linqing Wang,&nbsp;Zhenxing Shen,&nbsp;Di Lu,&nbsp;Hongmei Xu,&nbsp;Ningning Zhang,&nbsp;Yali Lei,&nbsp;Qian Zhang,&nbsp;Xin Wang,&nbsp;Qiyuan Wang,&nbsp;Junji Cao","doi":"10.1007/s10874-019-09393-2","DOIUrl":"https://doi.org/10.1007/s10874-019-09393-2","url":null,"abstract":"<p>A total of 30 precipitation samples were collected at a remote site of Qinghai Lake in the northeastern Tibetan Plateau, China, from June to August 2010. All samples were analyzed for major cations (NH₄⁺, Na⁺, K⁺, Ca²⁺, and Mg²⁺) and anions (F^?, Cl^?, NO₃^?, and SO₄^2?), electric conductivity (EC), pH, dissolved organic carbon (DOC), and oxygen isotopic composition (δ¹⁸O). The volume-weighted mean (VWM) values of pH and EC in the precipitation samples were 7.2 and 19.0?μs?cm^?1. Ca²⁺ was the dominant cation in precipitation with a VWM of 116.9 μeq L^?1 (1.6–662.9 μeq L^?1), accounting for 45.7% of total ions in precipitation. SO₄^2? was the predominant anion with a VWM of 32.7 μeq L^?1, accounting for 47.1% of the total anions. The average precipitation DOC was 1.4?mg?L^?1, and it shows a roughly negative power function with the precipitation amount. The values of δ¹⁸O in the rainwater in Qinghai Lake varied from ?13.5‰ to ?3.9‰ with an average of ?8.1‰. The enrichment factor analysis indicates that crustal materials from continental dust were the major sources for Ca²⁺ in the precipitation samples. The high concentration of Ca²⁺ in the atmosphere played an important role in neutralizing the acidity of rainwater in Qinghai Lake area. Cluster analysis of air-mass trajectories indicates that the air masses associated with northeast and east had high values of NH₄⁺, SO₄^2?, and NO₃^?, whereas large Ca²⁺ loading was related to the air mass from west.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 3","pages":"229 - 243"},"PeriodicalIF":2.0,"publicationDate":"2019-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09393-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4687002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ground-based observation of lightning-induced nitrogen oxides at a mountaintop in free troposphere","authors":"Ryuichi Wada,&nbsp;Y. Sadanaga,&nbsp;S. Kato,&nbsp;N. Katsumi,&nbsp;H. Okochi,&nbsp;Y. Iwamoto,&nbsp;K. Miura,&nbsp;H. Kobayashi,&nbsp;M. Kamogawa,&nbsp;J. Matsumoto,&nbsp;S. Yonemura,&nbsp;Y. Matsumi,&nbsp;M. Kajino,&nbsp;S. Hatakeyama","doi":"10.1007/s10874-019-09391-4","DOIUrl":"https://doi.org/10.1007/s10874-019-09391-4","url":null,"abstract":"<p>Lightning is an important source of nitrogen oxides (LNO_x). The actual global production of LNO_x is still largely uncertain. One of the reasons for this uncertainty is the limited available observation data. We measured the concentrations of total reactive nitrogen (NO_y), nitric oxide (NO) and nitrogen dioxides (NO₂) and then obtained NO_x oxidation products (NO_z: NO_z?=?NO_y - NO_x) at a station at the top of Mount Fuji (3776?m?a.s.l.) during the summer of 2017. Increases in NO_y and NO₂ were observed on 22 August 2017. These peaks were unaccompanied by increases in CO, which suggested that the observed air mass did not contain emissions from combustion. The backward trajectories of the above air mass indicated that it moved across areas where lightning occurred. The NO_y concentration was also calculated by using a chemical transport model, which did not take NO_x produced by lightning into account. Therefore, the NO_y concentration due to lightning can be inferred by subtracting the calculated NO_y from the observed NO_y concentrations. The concentration of NO_y at 13:00 on 22 August 2017 originating from lightning was estimated to be 1.11?±?0.02 ppbv, which comprised 97?±?2% of the total NO_y concentration. The fractions of NO₂ and NO_z in the total NO_y were 0.54?±?0.01 and 0.46?±?0.03, respectively. The NO concentration was below the detection limit. We firstly observed increase of concentrations of NO_y originating from lightning by ground-based observation and demonstrated the quantitative estimates of LNO_x using model-based calculation.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 2","pages":"133 - 150"},"PeriodicalIF":2.0,"publicationDate":"2019-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09391-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4583730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PM2.5 and PM10 in the urban area of Naples: chemical composition, chemical properties and influence of air masses origin","authors":"Elena Chianese,&nbsp;Giuseppina Tirimberio,&nbsp;Angelo Riccio","doi":"10.1007/s10874-019-09392-3","DOIUrl":"https://doi.org/10.1007/s10874-019-09392-3","url":null,"abstract":"<p>In order to investigate particulate matter characteristics in the urban area of Naples, South of Italy, PM₁₀ and PM_2.5 chemical composition and properties were determined; in particular, ionic composition (Na⁺, K⁺, NH₄⁺, Mg²⁺, Ca²⁺, HCOO-, CH₃COO^?, Cl^?, NO₂^?, NO₃^?, SO₄^2?, C₂O₄^2?) and concentration of specific metals (Pb, Cd, Cu and Zn) were evaluated in association with an air masses trajectories study. Information on major ions was used to conduct the ionic balance and to evaluate sea salt and non-sea salt contributions; furthermore, the study on metals concentration allowed to distinguish the contribution of anthropic sources while their chemical behaviour (solubility and leachability) was considered in order to highlight the presence of different chemical forms. In the period of interest (June 2015), daily averages PM concentrations were below the limit of 25?μg/m³ for PM_2.5 and 50?μg/m³for PM₁₀; moreover, for both fractions, the most abundant ionic species was SO₄^2?followed by NO₃^?. Ionic balance indicated that non-sea salt contribution accounted for the great part of Ca²⁺, SO₄^2? and K⁺ while secondary inorganic aerosol accounted for about 5% of total ionic fraction. As expected, the most abundant metal was zinc (about 41?ng/m³ and 44?ng/m³in PM_2.5 and PM_10, respectively), while cadmium, copper and lead were at very low concentrations, in the range of 0.01–0.47?ng/m³; leachability reached values of 40% for copper in both PM fractions, in contrast with zinc that showed the lowest leachability, corresponding to 6% for PM_2.5 fraction. The study on air masses trajectories indicated a change on ionic composition and chemical properties, varying from a condition with air masses coming from Eastern Europe, characterised also by higher concentrations of both PM_2.5 and PM₁₀, a prevalence of secondary aerosol and metals showing minor solubility and leachability, to a condition with air masses coming from North-west region, with characteristics opposed to the previous ones.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 2","pages":"151 - 169"},"PeriodicalIF":2.0,"publicationDate":"2019-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09392-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4398281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of polar organic aerosols at a regional background site in southern Africa","authors":"Wanda Booyens,&nbsp;Johan P. Beukes,&nbsp;Pieter G. Van Zyl,&nbsp;Jose Ruiz-Jimenez,&nbsp;Matias Kopperi,&nbsp;Marja-Liisa Riekkola,&nbsp;Miroslav Josipovic,&nbsp;Ville Vakkari,&nbsp;Lauri Laakso","doi":"10.1007/s10874-019-09389-y","DOIUrl":"https://doi.org/10.1007/s10874-019-09389-y","url":null,"abstract":"<p>A recent paper reported GCxGC-TOFMS analysis used for the first time in southern Africa to tentatively characterise and semi-quantify ~1000 organic compounds in aerosols at Welgegund – a regional background atmospheric monitoring station. Ambient polar organic aerosols characterised are further explored in terms of temporal variations, as well as the influence of meteorology and sources. No distinct seasonal pattern was observed for the total number of polar organic compounds tentatively characterised and their corresponding semi-quantified concentrations (sum of the normalised response factors, ∑NRFs). However, the total number of polar organic compounds and ∑NRFs between late spring and early autumn seemed relatively lower compared to the period from mid-autumn to mid-winter, while there was a period during late winter and early spring with significantly lower total number of polar organic compounds and ∑NRFs. Relatively lower total number of polar organic compounds and corresponding ∑NRFs were associated with fresher plumes from a source region relatively close to Welgegund. Meteorological parameters indicated that wet removal during late spring to early autumn also contributed to lower total numbers of polar organics and associated ∑NRFs. Increased anticyclonic recirculation and more pronounced inversion layers contributed to higher total numbers of polar organic species and ∑NRFs from mid-autumn to mid-winter, while the influence of regional biomass burning during this period was also evident. The period with significantly lower total number of polar organic compounds and ∑NRFs was attributed to fresh open biomass burning plumes occurring within proximity of Welgegund, consisting mainly of volatile organic compounds and non-polar hydrocarbons. Multiple linear regression substantiated that the temporal variations in polar organic compounds were related to a combination of the factors investigated in this study.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 2","pages":"89 - 113"},"PeriodicalIF":2.0,"publicationDate":"2019-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09389-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5105858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A one year study of functionalised medium-chain carboxylic acids in atmospheric particles at a rural site in Germany revealing seasonal trends and possible sources","authors":"M. Teich,&nbsp;D. van Pinxteren,&nbsp;H. Herrmann","doi":"10.1007/s10874-019-09390-5","DOIUrl":"https://doi.org/10.1007/s10874-019-09390-5","url":null,"abstract":"<p>This study presents a yearlong data set of 28 medium-chain functionalised carboxylic acids (C5 to C10) in atmospheric aerosol particles (PM₁₀) from a German rural measurement station, which is analysed to obtain seasonal trends and evidences for possible sources of these rarely studied compounds. The analysed carboxylic acids were divided into four main groups: <b>(I)</b> functionalised aliphatic monocarboxylic acids, <b>(II)</b> functionalised aromatic monocarboxylic acids, <b>(III)</b> non-functionalised and functionalised aliphatic dicarboxylic acids, and <b>(IV)</b> aromatic dicarboxylic acids. A concentration maximum in summer was observed for aliphatic carboxylic acids, indicating mainly photochemical formation processes. For example, the highest mean summer concentrations were observed for 4-oxopentanoic acid (4.1?ng?m^?3) in group I and for adipic acid (10.3?ng?m^?3) in group III. In contrast, a concentration maximum in winter occurred for aromatic carboxylic acids, hinting at anthropogenic sources like residential heating. The highest mean winter concentrations were observed for 4-hydroxybenzoic acid (2.4?ng?m^?3) in group II and for phthalic acid (5.8?ng?m^?3) in group IV. For the annual mean concentrations, highest values were found for adipic acid and 4-oxopimelic acids with 7.8?ng?m^?3 and 6.1?ng?m^?3, respectively. The concentrations of oxodicarboxylic acids exceeded those of their corresponding unsubstituted form. Accordingly, straight-chain dicarboxylic acids might act as precursor compounds for their respective oxygenated forms. Similarly, unsubstituted monocarboxylic acids are possible precursors for functionalised aliphatic monocarboxylic acids. The present study contributes to the speciation of organic content on a molecular level of atmospheric particles, as well as giving hints for possible sources for these carboxylic acids.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 2","pages":"115 - 132"},"PeriodicalIF":2.0,"publicationDate":"2019-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09390-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4371659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal variations and source apportionment of water-soluble inorganic ions in PM2.5 in Nanjing, a megacity in southeastern China","authors":"Xiaoyu Zhang,&nbsp;Xin Zhao,&nbsp;Guixiang Ji,&nbsp;Rongrong Ying,&nbsp;Yanhong Shan,&nbsp;Yusuo Lin","doi":"10.1007/s10874-019-09388-z","DOIUrl":"https://doi.org/10.1007/s10874-019-09388-z","url":null,"abstract":"<p>Daily PM_2.5 samples were collected in Nanjing, a megacity in southeastern China, for a period of one-half of a month during every season from 2014~2015. Mass concentrations of nine water soluble inorganic ions (F^?, Cl^?, SO₄^2?, NO₃^?, Na⁺, NH₄⁺, K⁺, Mg²⁺ and Ca²⁺) were determined using ion chromatography to identify the chemical characteristics and potential sources of PM_2.5. The mass concentrations of daily PM_2.5 ranged from 31.0 to 242.9?μg?m^?3, with an annual average and standard deviation of 94.4?±?31.1?μg?m^?3. The highest seasonal average of PM_2.5 concentrations was observed during winter (108.5?±?31.8?μg?m^?3), and the lowest average was observed during summer (85.0?±?22.6?μg?m^?3). The annual average concentration of total water soluble inorganic ions was 39.82?μg?m^?3, accounting for 44.4% of the PM_2.5. The seasonal variation in water soluble inorganic ions in PM_2.5 reached its maximum during autumn and reached its minimum during spring. Sulfate, nitrate and ammonium were the dominant water soluble inorganic species, with their combined proportion of 82.0% of the total water soluble inorganic ions and 36.8% of the fine particles. Seasonal variations in aerosol acidity and chemical forms of secondary inorganic ions were discussed. The average ratio of NO₃^?/SO₄^2? was 0.95. According to the results of principal component analysis, secondary sources, burning processes, and airborne dust were the dominant potential sources of PM_2.5 in Nanjing.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 1","pages":"73 - 88"},"PeriodicalIF":2.0,"publicationDate":"2019-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-09388-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4900907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dissolved organic carbon in summer precipitation and its wet deposition flux in the Mt. Yulong region, southeastern Tibetan Plateau","authors":"Hewen Niu,&nbsp;Shichang Kang,&nbsp;Xiaofei Shi,&nbsp;Guotao Zhang,&nbsp;Shijin Wang,&nbsp;Tao Pu","doi":"10.1007/s10874-019-9385-8","DOIUrl":"https://doi.org/10.1007/s10874-019-9385-8","url":null,"abstract":"<p>Dissolved organic carbon (DOC) is an important organic pollutant in the air-water carbon cycle system, potentially influencing the global climate. In this study, 204 rainwater samples from five sampling stations in the Mt. Yulong region were synchronously collected from June to September in 2014. We comprehensively investigated the sources and wet deposition of DOC in summer precipitation. The average concentrations of DOC at five stations ranged from 0.74 to 1.31?mg?L^?1. The mass absorption efficiency (MAE) of rainwater DOC evaluated at 365?nm was 0.43?±?0.32?m²?g^?1. Backward trajectory analyses indicated that the southwest advection air parcel accounting for 46% of precipitation events, while the corresponding average concentration of rainwater DOC was 1.25?±?0.56?mg C L^?1. In addition to the local or regional contribution, large amount of atmospheric pollutants were transported from South Asia and Southeast Asia to the Mt. Yulong region, both of which had exerted great influence on the regional atmospheric environment. For the first time, the annual wet deposition of DOC in the Mt. Yulong region was estimated and determined to be 1.99?g C m^?2?year^?1. This is significant because the deposition of DOC on glaciers has great influence on surface albedo of snow and glacier melt. This study can bridge the gap of rainwater DOC research between the Mt. Yulong region and the southeast of Tibetan Plateau (TP), which has significant implications for better understanding the relationship of DOC deposition and glacial shrink in the TP.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 1","pages":"1 - 20"},"PeriodicalIF":2.0,"publicationDate":"2019-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-9385-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4786954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elevated Barium concentrations in rain water from east-coast of India: role of regional lithology","authors":"Gyana Ranjan Tripathy,&nbsp;Smruti Mishra,&nbsp;Mohd Danish,&nbsp;Kirpa Ram","doi":"10.1007/s10874-019-9387-6","DOIUrl":"https://doi.org/10.1007/s10874-019-9387-6","url":null,"abstract":"<p>Alkaline earth metals act as dominating acid-neutralizing species in atmosphere and hence, regulate the rain water chemistry significantly. In this contribution, concentrations of these metals (Mg, Ca, Sr and Ba) and other major ions in rain water samples, collected during south-west monsoon of year 2017, from a coastal location (Berhampur) in eastern part of India have been analyzed to trace their provenances and controlling factors. The chemical compositions of rain water reveal oceanic and continental supply of Mg and Sr to the site, whereas Ca and Ba are pre-dominantly supplied through continental sources. The dominancy of continental fluxes at this coastal site is mainly due to particulate fluxes from regional lithologies and favorable wind pattern for long-range transport from south-western/western directions. An inverse model involving chemical mass balance between rain water composition and its possible sources have been adopted in this study to quantify the source(s) contributions. These model results show that the continental Mg is mainly derived from long-range transport of mafic minerals from Deccan Traps (40?±?21%) with sub-ordinate contribution (15?±?6%) from regional lithologies. On average, about 70% of rain water Ca at Berhampur is derived from carbonates, whereas most of the Ba (~95%) is supplied from regional silicates (charnockites and khondalites). Owing to faster dissolution kinetics of these silicates with higher Ba content, the silicates contribute most of the rain water Ba concentration over this region. The median Ba content (29 nM) at this location is systematically higher than available literature Ba data for rain water worldwide (1-22 nM). The observed higher concentrations of Ba, a micronutrient, in rain water emphasize important role of regional lithology in the biogeochemical cycling of nutrients over the region via wet deposition.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"76 1","pages":"59 - 72"},"PeriodicalIF":2.0,"publicationDate":"2019-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-019-9387-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4336156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}