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Detection of aerosols in Antarctica From Long-Range Transport of the 2009 Australian Wildfires

JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 2020年第23期125卷 1-17页

作者： Jumelet, J. Klekociuk, A. R. Alexander, S. P. Bekki, S. Hauchecorne, A. Vernier, J. P. Fromm, M. Keckhut, P. LATMOS CNRS IPSL UPMC UVSQ Paris France Australian Antarctic Div Kingston Australia NASA Langley Res Ctr Hampton VA 23665 USA Naval Res Lab Washington DC 20375 USA

We analyze the long-range transport to high latitudes of a smoke particle filament originating from the extratropics plume after the Australian wildfires colloquially known as "Black Saturday" on 7 February and report the first Antarctic stratospheric lidar characterization of such aerosols. Using a high-resolution transport/microphysical model, we show that the monitoring cloud/aerosol lidar instrument operating at the French Antarctic station Dumont d'Urville (DDU, 66 degrees S to 140 degrees E) recorded a signature of those aerosols. The 532 nm scattering ratio of this filament is comparable to typical moderate stratospheric volcanic plume, with values between 1.4 and 1.6 on the first and third days of March above DDU station at around the 14 and 16 km altitude, respectively. A dedicated model is described and its ability to track down fine optical signatures is validated against Antarctic lidar elastic aerosol and DIAL ozone measurements. Using 1 month of tropical Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) data to support a relatively simple microphysical scheme, we report modeled aerosol presence above DDU station after advection of the aerosol size distribution. In situ measurements also report associated positive ozone anomaly. This case study provides evidence that biomass burning events injecting significant amounts of material up to stratospheric altitudes can be transported toward high latitudes. We highlight a potential imprint of smoke particles on the Antarctic atmosphere over larger time scales. Any underestimation of the global impact of such deep particle transport will lead to uncertainties in modeling the associated chemical or radiative effects, especially in polar regions, where specific microphysical and chemical processes take place.

关键词： lidar Antarctica bushfires aerosols

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Spatiotemporal Analysis of Multi-Year Wildfires and Emissions of Trace Gases and aerosols in Russia Based on Satellite Data

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IZVESTIYA ATMOSPHERIC AND OCEANIC PHYSICS 2020年第12期56卷 1457-1469页

作者： Bondur, V. G. Voronova, O. S. Cherepanova, E. V. Tsidilina, M. N. Zima, A. L. AEROCOSMOS Res Inst Aerosp Monitoring Moscow 105064 Russia

An analysis is performed of the annual and intraseasonal dynamics of wildfire areas and volumes of trace gas components (CO, CO2, CH4, NO, and NO2) and fine aerosols (PM2.5) caused by wildfires in Russia and its large regions over 19 years. The analysis is based on results from satellite monitoring, allowing for the effect anomalies in weather and climate have on the intensity of fires. It is shown that the average size of areas burned monthly in the European part of Russia fell by half in April, May, and September, and by a factor of four in July and August over the period 2011 to 2019, compared to the respective months in 2001-2010. A negative trend is observed for spring and autumn from 2010 to 2019 in the Siberian and Ural federal districts, along with a summer increase in fire areas. It is found that over 19 years, the dynamics of the burned areas is weakly defined for most months of the fire season in the Far Eastern Federal District. Extremely high volumes of emissions of different trace gases (including CO and CO2) and aerosols caused by wildfires were detected in the Siberian Federal District in 2003 and 2012.

关键词： wildfires remote sensing satellite data satellite monitoring emissions trace gases aerosols

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Nuclear Magnetic Resonance Aerosolomics: A Tool for Analysis of Polar Compounds in Atmospheric aerosols

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ACS OMEGA 2020年第36期5卷 22750-22758页

作者： Hornik, Stepan Sykora, Jan Schwarz, Jaroslav Zdimal, Vladimir Czech Acad Sci Inst Chem Proc Fundamentals Vvi Prague 16502 6 Czech Republic Univ Chem & Technol Dept Analyt Chem Prague 16628 6 Czech Republic

Nuclear magnetic resonance aerosolomics was proposed as a new approach to the analysis of the water-soluble organic compound fraction in aerosol particulate matter. The identification of individual compounds is based on a comparison of precise chemical shifts in the H-1 NMR spectrum with the signals in the standards library. For this purpose, Chenomx metabolomics software and a comprehensive spectra library of 150 compounds known from chemistry of aerosols were used. This approach enabled the identification of 60 compounds in real aerosol samples collected at a suburban site in Prague. Using the metabolomic spectra library, three new compounds were identified in aerosols for the first time, and an association of four other compounds to the atmospheric particulate matter was confirmed. The obtained concentration profiles of all identified chemical individuals were subsequently subjected to advanced statistical analysis. NMR aerosolomics clearly differentiates between summer and winter aerosol samples via multivariate statistical analysis and revealed some interesting trends in composition, according to aerosol particle size. Furthermore, the univariate statistical analysis was applied to highlight compounds responsible for the group separation, and possible sources of these compounds were suggested.

关键词： Carbohydrates aerosols Nuclear magnetic resonance spectroscopy Mathematical methods Particulate matter

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Evaluating Organic Aerosol Sources and Evolution with a Combined Molecular Composition and Volatility Framework Using the Filter Inlet for Gases and aerosols (FIGAERO)

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ACCOUNTS OF CHEMICAL RESEARCH 2020年第8期53卷 1415-1426页

作者： Thornton, Joel A. Mohr, Claudia Schobesberger, Siegfried D'Ambro, Emma L. Lee, Ben H. Lopez-Hilfiker, Felipe D. Stockholm Univ Dept Environm Sci S-10691 Stockholm Sweden Univ Eastern Finland Dept Appl Phys Kuopio 70210 Finland Oak Ridge Inst Sci & Educ Oak Ridge TN 37831 USA Univ Washington Dept Atmospher Sci Seattle WA 98195 USA Tofwerk AG CH-3645 Thun Switzerland

The complex array of sources and transformations of organic carbonaceous material that comprises an important fraction of atmospheric fine particle mass, known as organic aerosol, has presented a long running challenge for accurate predictions of its abundance, distribution, and sensitivity to anthropogenic activities. Uncertainties about changes in atmospheric aerosol particle sources and abundance over time translate to uncertainties in their impact on Earth's climate and their response to changes in air quality policy. One limitation in our understanding of organic aerosol has been a lack of comprehensive measurements of its molecular composition and volatility, which can elucidate sources and processes affecting its abundance. Herein we describe advances in the development and application of the Filter Inlet for Gases and aerosols (FIGAERO) coupled to field-deployable High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometers (HRToF-CIMS). The FIGAERO HRToFCIMS combination broadly probes gas and particulate OA molecular composition by using programmed thermal desorption of particles collected on a Teflon filter with subsequent detection and speciation of desorbed vapors using inherently quantitative selected-ion chemical ionization. The thermal desorption provides a means to obtain quantitative insights into the volatility of particle components and thus the physicochemical nature of the organic material that will govern its evolution in the atmosphere. In this Account, we discuss the design and operation of the FIGAERO, when coupled to the HRToF-CIMS, for quantitative characterization of the molecular-level composition and effective volatility of organic aerosol in the laboratory and field. We provide example insights gleaned from its deployment, which improve our understanding of organic aerosol sources and evolution. Specifically, we connect thermal desorption profiles to the effective equilibrium saturation vapor concentration and enthalpy of vapo

关键词： Desorption Thermodynamic properties Evaporation aerosols Oxidation

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Atmospheric pollution assessment near potential source of natural aerosols in the South Gobi Desert region, China

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GISCIENCE & REMOTE SENSING 2020年第2期57卷 227-244页

作者： Filonchyk, Mikalai Hurynovich, Volha Yan, Haowen Yang, Shuwen Lanzhou Jiaotong Univ Fac Geomat Lanzhou Peoples R China Gansu Prov Engn Lab Natl Geog State Monitoring Lanzhou Peoples R China

Rapid economic growth, a high degree of urbanization and the proximity of a large number of desert and semidesert landscapes can have a significant impact on the atmosphere of adjacent territories, leading to high levels of atmospheric pollution. Therefore, identifying possible sources of atmospheric pollution is one of the main tasks. In this study, we carried out an analysis of spatial and temporal characteristics of five main atmospheric pollutants (PM2.5, PM10, SO2, NO2, and CO) near potential source of natural aerosols, affecting seven cities (Wuhai, Alashan, Wuzhong, Zhongwei, Wuwei, Jinchang, Zhangye), located in immediate proximity to the South Gobi deserts. The results, obtained for the period from 1 January 2016 to 31 December 2018, demonstrate total concentrations of PM2.5 and PM10 are 38.2 +/- 19.5 and 101 +/- 80.7 mu g/m(3) exceeding the same established by the Chinese National Ambient Air Quality Standard (CNAAQS), being 35 and 70 mu g/m(3), respectively. Based on the data from Moderate Resolution Imaging Spectroradiometer (MODIS) for the whole period, Clean Continental (71.49%) and Mixed (22.29%) types of aerosols prevail in the region. In the spring and winter seasons maximum concentrations of pollutants and high values of Aerosol Optical Depth (AOD) in the region atmosphere are observed. PM2.5 and PM10 ratio shows the presence of coarse aerosols in the total content with value 0.43. The highest concentrations of pollutants were in the period of dust storms activity, when PM2.5 and PM10 content exceeded 200 and 1000 mu g/m(3), and AOD value exceeded 1. UV Aerosol Index (UVAI), Aerosol Absorbing Optical Depth (AAOD), and Single Scattering Albedo (SSA), obtained from Ozone Monitoring Instrument (OMI), demonstrate the high content of dust aerosols in the period of sandstorms. Analysis of backward trajectories shows that dust air masses moved from North to Northwest China, affecting large deserts such as Taklamakan, Gurbantunggut, Badain Jaran, Tengger,

关键词： Air pollutants dust storm aerosols Gobi Desert remote sensing air quality

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Microbial aerosols New Diagnostic Specimens for Pulmonary Infections

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CHEST 2020年第3期157卷 540-546页

作者： Fennelly, Kevin P. Acuna-Villaorduna, Carlos Jones-Lopez, Edward Lindsley, William G. Milton, Donald K. NHLBI NIH Bldg 10 Bethesda MD 20892 USA Boston Med Ctr Boston MA USA Boston Univ Sch Med Boston MA 02118 USA Ctr Dis Control & Prevent NIOSH Morgantown WV USA Univ Maryland Sch Publ Hlth Maryland Inst Appl Environm Hlth College Pk MD 20742 USA

Pulmonary infections are important causes of global morbidity and mortality, but diagnostics are often limited by the ability to collect specimens easily, safely, and in a cost-effective manner. We review recent advances in the collection of infectious aerosols from patients with TB and with influenza. Although this research has been focused on assessing the infectious potential of such patients, we propose that these methods have the potential to lead to the use of patient-generated microbial aerosols as noninvasive diagnostic tests of disease and tests of infectiousness.

关键词： aerosols infectious disease influenza microbial TB

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Water Adsorption vs Phase Transition of aerosols Monitored by a Quartz Crystal Microbalance

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ACS OMEGA 2020年第49期5卷 31858-31866页

作者： Chao, Hsing-Ju Huang, Wei-Chieh Chen, Chia-Li Chou, Charles C-K Hung, Hui-Ming Natl Taiwan Univ Dept Atmospher Sci Taipei 10617 Taiwan Acad Sinica Res Ctr Environm Changes Taipei 11529 Taiwan

A quartz crystal microbalance (QCM) with a high sensitivity of 0.1 ng was applied to monitor the oscillation frequency variation (Delta f) of standard single species, two-component systems with typical ambient aerosol compositions, and ambient aerosol filter samples as a function of relative humidity (RH) and determine their deliquescence RH (DRH) and phase transition. Delta f is associated with the adsorption or desorption process of water molecules for solid samples and physical properties of the sample film during solid-to-aqueous phase transition (deliquescence). During the pre-deliquescence stage, the water adsorption process led to the increased mass with decreasing Delta f, especially for the hydrates such as MgCl2 and Ca(NO3)(2), which have more than 20% and 40% increased mass, respectively. The water adsorption process might cause a mass deviation of ambient particulate matter measurement using similar instrument principles. During the deliquescence stage, the observed rapid increasing Delta f with RH was caused by a significant change in the physical properties (such as density and viscosity) of the sample film. The determined DRH for a given single-component system is consistent with the results estimated from the thermodynamic models. For a complex system, the QCM can determine the DRH 1st well as the eutonic point and track the possible variation of the physical properties of inorganic or with organic acid mixture systems. During the post-deliquescence stage, the gradual increasing trend of Delta f with RH for Ca(NO3)(2) and an external mixture of NaCl-Ca(NO3)(2) was mainly contributed by a stronger RH dependent of physical properties for Ca(NO3)(2) (aq). Overall, this study provides the possible physical properties variation of common aerosol composition as a function of RH, which was consistent with the results calculated from the thermodynamic models. The stronger water adsorption for MgCl2 and Ca(NO3)(2) with solid-like viscosity at RH < DRH might l

关键词： Anions Adsorption Mixtures aerosols Phase transitions

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Significant Decline in aerosols in the Mixing Layer in Beijing from 2015 to 2020: Effects of Regional Coordinated Air Pollution Control

SSRN

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SSRN 2022年

作者： Zhu, Zhenyu Tang, Guiqian Wu, Liping Wang, Yinghong Liu, Baoxian Li, Qian Hu, Bo Bai, Weihua Wang, Yuesi School of Environment and Municipal Engineering Tianjin Chengjian University Tianjin300384 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing100029 China Beijing Key Laboratory of Airborne Particulate Matter Monitoring Technology Beijing Municipal Ecological Environmental Monitoring Center Beijing100048 China National Space Science Center Chinese Academy of Sciences NSSC/CAS Beijing100190 China Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen361021 China University of Chinese Academy of Sciences Beijing100049 China

Beijing's air quality has improved significantly since the implementation of the Air Pollution Prevention and Control Action Plan in 2013, but the local and regional contributions to this improvement have rarely been studied. Here, the vertical profile of the atmospheric backscattering coefficient (ABC) was measured by a ceilometer in Beijing from 2015 to 2020. The results show that the ABC in Beijing decreased the most at ground level from 2015 to 2020, decreasing 51.4 %. Interannual variability decreased with height, and no noticeable change was found in the height range above 600 m. The most apparent declines occurred in autumn and winter, with decreases greater than 60 %, and the minimum decrease occurred in summer, with a reduction of only 20.0 %. To analyze the reasons for the autumn and winter declines, we divided the whole day into four periods according to the evolution characteristics of the atmospheric boundary layer. The significant decrease in the backscattering coefficient near the ground during the daytime confirms the effect of local emission reductions. In contrast, the considerable decreases in the backscattering coefficient measured at different heights in the midday mixing layer demonstrate the contribution of regional transport reduction. The above research results confirm the importance of regional coordinated air pollution control. © 2022, The Authors. All rights reserved.

关键词： aerosols

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Efficacy of Do-it-Yourself Air Filtration Units in Reducing Exposure to Simulated Respiratory aerosols

SSRN

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SSRN 2022年

作者： Derk, Raymond C. Coyle, Jayme P. Lindsley, William G. Blachere, Francoise M. Lemons, Angela R. Service, Samantha K. Martin, Stephen B. Mead, Kenneth R. Fotta, Steven A. Reynolds, Jeffrey S. McKinney, Walter G. Sinsel, Erik W. Beezhold, Donald H. Noti, John D. Health Effects Laboratory Division National Institute for Occupational Safety and Health Centers for Disease Control and Prevention 1000 Fredrick Lane MorgantownWV26508 United States Respiratory Health Division National Institute for Occupational Safety and Health Centers for Disease Control and Prevention 1000 Fredrick Lane MorgantownWV26505 United States Division of Field Studies and Engineering National Institute for Occupational Safety and Health Centers for Disease Control and Prevention CincinnatiOH45226 United States

SARS-CoV-2 can be spread by aerosols expelled by infected people when they cough, talk, sing, or exhale. Exposure to these aerosols while indoors can be reduced by portable air filtration units (air cleaners). Homemade or Do-It-Yourself (DIY) air filtration units are a popular alternative to commercially produced devices, but performance data is limited. Our study used a speaker-audience model to examine the efficacy of two popular types of DIY air filtration units, the Corsi-Rosenthal cube and a modified Ford air filtration unit, in reducing exposure to simulated respiratory aerosols within a mock classroom. Experiments were conducted using four breathing simulators at different locations in the room, one acting as the respiratory aerosol source and three as recipients. Optical particle spectrometers were used to monitor simulated respiratory aerosol particles (0.3 to 3 μm) as they dispersed throughout the room. Using two DIY cubes (in the front and back of the room) increased the air change rate as much as 12.4 over room ventilation, depending on filter thickness and fan airflow. Using multiple linear regression, each unit increase of air change reduced exposure by 10%. Increasing the number of filters, filter depth, and fan airflow significantly enhanced the air change rate, which resulted in exposure reductions of up to 73%. Our results show DIY air filtration units can be an effective means of reducing aerosol exposure. However, they also show performance of DIY units can vary considerably depending upon their design, construction, and positioning, and users should be mindful of these limitations. © 2022, The Authors. All rights reserved.

关键词： aerosols

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Active aerosols

arXiv

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arXiv 2022年

作者： Rohde, Charles A. Charipar, Kristin M. Johns, Paul Porter, Ashlin G. Greybush, Nicholas J. Fontana, Jake U.S. Naval Research Laboratory 4555 Overlook Ave. SW WashingtonDC20375 United States

We report the dynamics and control of the orientational and positional order of ensembles of gold nanorods suspended in air at standard temperature and pressure using externally applied electric fields, demonstrating an active aerosol. Light filter, valve and gradient responses are shown, establishing active aerosols as a unique type of optical element we term component-less optics. © 2022, CC BY.

关键词： aerosols

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