Download or read book Optical and Physical Properties of Biomass Burning Aerosols written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Properties of Biomass Burning Aerosols Measured During FLAME 4 written by Rudra Prasad Pokhrel and published by . This book was released on 2015 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical properties of biomass burning aerosol at three different wavelengths (405, 532, and 660 nm) have been measured during the Fourth Fire Lab at Missoula Experiment (FLAME-4), which took place at the Fire Science Laboratory in Missoula, Montana, in October and November, 2012. During the experiment, absorption and extinction coefficients of aerosol emissions from biomass burning were measured. A photo-acoustic absorption spectrometer (PAS) measured the absorption coefficient of dry and denuded aerosol while a cavity ring-down spectrometer (CRDS) measured the extinction coefficient of dry and denuded aerosol. During the experiment, a wide range of fuels that represent significant sources of biomass emissions from different parts of world were burned. Fuels included trees, grasses, shrubs and peat. Fuels were burned in two different ways namely stack burns which allowed for measurements during different phases of the burn (flaming vs. smoldering) and room burns which allowed for detailed measurements of well mixed smoke from all phases of the fire. Single scattering albedo (SSA) and absorption angstrom exponent (AAE) values for the biomass burning aerosols have been calculated are now represented. Eight fuels were combusted during 20 individual stack burns and 12 fuels were analyzed during 21 room burns. Parameterizations of SSA and AAE as functions of modified combustion efficiency (MCE) and a proxy for the ratio of black carbon to organic carbon mass (BC:OA proxy) have been developed. The BC:OA proxy is found to shown better correlation to both SSA and AAE than does MCE. Combined of the stack and room burn results (41 individual burns and 12 different fuels) show that the BC:OA proxy can explain 94% of the variability in SSA and 70 % of the variability in AAE while MCE can only explain 40 % and 54 % of the variability in SSA and AAE, respectively.

Download or read book Investigation of the Optical and Cloud Forming Properties of Pollution Biomass Burning and Mineral Dust Aerosols written by Yong Seob Lee and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes the use of measured aerosol size distributions and size-resolved hygroscopic growth to examine the physical and chemical properties of several particle classes. The primary objective of this work was to investigate the optical and cloud forming properties of a range of ambient aerosol types measured in a number of different locations. The tool used for most of these analyses is a differential mobility analyzer / tandem differential mobility analyzer (DMA / TDMA) system developed in our research group. To collect the data described in two of the chapters of this dissertation, an aircraft-based version of the DMA / TDMA was deployed to Japan and California. The data described in two other chapters were conveniently collected during a period when the aerosol of interest came to us. The unique aspect of this analysis is the use of these data to isolate the size distributions of distinct aerosol types in order to quantify their optical and cloud forming properties. I used collected data during the Asian Aerosol Characterization Experiment (ACE-Asia) to examine the composition and homogeneity of a complex aerosol generated in the deserts and urban regions of China and other Asian countries. An aircraft-based TDMA was used for the first time during this campaign to examine the size-resolved hygroscopic properties of the aerosol. The Asian Dust Above Monterey (ADAM-2003) study was designed both to evaluate the degree to which models can predict the long-range transport of Asian dust, and to examine the physical and optical properties of that aged dust upon reaching the California coast. Aerosol size distributions and hygroscopic growth were measured in College Station, Texas to investigate the cloud nucleating and optical properties of a biomass burning aerosol generated from fires on the Yucatan Peninsula. Measured aerosol size distributions and size-resolved hygroscopicity and volatility were used to infer critical supersaturation distributions of the distinct particle types that were observed during this period. The predicted cloud condensation nuclei concentrations were used in a cloud model to determine the impact of the different aerosol types on the expected cloud droplet concentration. RH-dependent aerosol extinction coefficients were also calculated.

Download or read book Optical Properties of Aerosol Emitted from Indoor Biomass Burning Cookstoves written by Samuel Arthur Whidden and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Properties and Radiative Forcing of Southern African Biomass Burning Aerosol written by Brian Indrek Magi and published by . This book was released on 2006 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiphase Environmental Chemistry in the Atmosphere written by Sherri W. Hunt and published by ACS Symposium. This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights new cross-disciplinary advances in aerosol chemistry that involve more than one phase, for example, unique chemical processes occurring on gas-solid and liquid-solid interfaces.

Download or read book Atmospheric Aerosols written by Claudio Tomasi and published by John Wiley & Sons. This book was released on 2017-03-20 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ein Blick auf die morphologischen, physikalischen und chemischen Eigenschaften von Aerosolen aus den unterschiedlichsten natürlichen und anthropogenen Quellen trägt zum besseren Verständnis der Rolle bei, die Aerosolpartikel bei der Streuung und Absorption kurz- und langwelliger Strahlung spielen. Dieses Fachbuch bietet Informationen, die sonst schwer zu finden sind, und vermittelt ausführlich die Kenntnisse, die erforderlich sind, um die mikrophysikalischen, chemischen und Strahlungsparameter zu charakterisieren, die bei der Wechselwirkung von Sonnen- und Erdstrahlen so überaus wichtig sind. Besonderes Augenmerk liegt auf den indirekten Auswirkungen von Aerosolen auf das Klima im Rahmen des komplexen Systems aus Aerosolen, Wolken und der Atmosphäre. Auch geht es vorrangig um die Wirkungen natürlicher und anthropogener Aerosole auf die Luftqualität und die Umwelt, auf die menschliche Gesundheit und unser kulturelles Erbe. Mit einem durchgängig lösungsorientierten Ansatz werden nicht nur die Probleme und Gefahren dieser Aerosole behandelt, sondern auch praktikable Lösungswege aufgezeigt.

Download or read book Characterization of Lignocellulosic Biomass and Constituent Burning Aerosols written by Luke P. McLaughlin and published by . This book was released on 2022 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomass burning (BB) is a globally occurring phenomenon that is understood to produce significant quantities of aerosols that have a broad range of local and global effects on humans and the environment. The quantities and properties of primary BB aerosol emissions are difficult to measure and predict, however, due to the natural complexity of the feedstocks and the evolved species, as well as the potential variability in local conditions. Near-source burn parameters, such as fuel composition, fuel mass loss rate, oxygen availability, burn phase, and dilution conditions, contribute to the complexity of BB and have been identified as factors that influence the quantities and physical, optical, and chemical properties of primary BB aerosols. The research presented in this dissertation seeks to elucidate new insights into the mechanisms of primary aerosol formation in naturally occurring biomass burning events by isolating the influences of near-source burn parameters on lignocellulosic biomass and constituent burning aerosols in a controlled laboratory environment. The produced data sets are well-defined and contribute validation data for current and future state-of-the-art aerosol formation models and submodels, as well as other experimental data. Lignocellulosic biomass and the major constituents of lignocellulosic biomass—hemicellulose, cellulose, and lignin—were pyrolyzed and oxidized using thermogravimetric analyzers (TGAs), and the highly repeatable aerosol emissions were characterized in terms of size-resolved number and mass emission factors, concentrations, size, and volatility. The aerosol emissions formed from biomass constituents were then compared to those of biomass, and a novel aerosol prediction model which utilizes superposition of individual constituent results and lignocellulosic biomass composition was developed to test a hypothesis that biomass burning aerosols can be predicted by lignocellulosic composition and constituent emissions when biomass and constituent aerosols are determined under similar conditions. Results showed that lignin and cellulose contents significantly contribute to BB aerosol formation, whereas hemicellulose contributions are less significant. Furthermore, lignin produced lower volatility aerosols compared to hemicellulose and cellulose. Increased absolute fuel mass loss rate was observed during oxidation compared to pyrolysis, and absolute fuel mass loss rate was found to positively correlate with median aerosol size. Increased oxygen availability during burning decreased mass and number emissions, and trends were attributed to complex influences of combustion chemistry and increased fuel mass loss rate from thermal feedback. In an air environment, aerosol number and mass emissions were found to increase and decrease, respectively, with successive pre-ignition pyrolysis, flaming, and post-flaming (smoldering) burn phases. Flaming combustion produced lower volatility emissions compared to pre-ignition pyrolysis and post-flaming smoldering. Results also showed a significant influence of dilution and thermodenuder (TD) temperature on particle size, number, and distribution, with increased dilution air and TD temperature decreasing total number and mass emissions. Regarding the developed superposition prediction model, simulated results well-predicted particle number and mass emission trends in each investigation. Prediction improvements were observed throughout the evolution of the work presented in this dissertation, and the successes and failures of the superposition model under the applied conditions were analyzed. Overall, the influence of near-source burn parameters on primary aerosol emissions was realized, and the potential of the superposition model to predict primary BB aerosol quantities and properties was demonstrated.

Download or read book Cavity Ring down Spectroscopy and the Retrieval of Aerosol Optical Properties from Biomass Burning During Flame2 written by Laura E. Mack and published by . This book was released on 2008 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aerosol Physical Properties and Emission Factors from Open Biomass Burning and Cookstove Emissions written by Oluwatobi Olamiposi Oke and published by . This book was released on 2015 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book I Global Simulations of Interactions Between Aerosols and Future Climate and II Sensitivity of Multiangle Imaging to the Optical and Microphysical Properties of Biomass Burning Aerosols written by Wei-Ting Chen and published by . This book was released on 2009 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atmospheric Aerosol Properties written by Kirill Ya. Kondratyev and published by Springer Science & Business Media. This book was released on 2006-08-29 with total page 595 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the first comprehensive analysis of how aerosols form in the atmosphere through in situ processes as well as via transport from the surface (dust storms, seas spray, biogenic emissions, forest fires etc.). Such an analysis has been followed by the consideration of both observation data (various field observational experiments) and numerical modeling results to assess climate impacts of aerosols bearing in mind that these impacts are the most significant uncertainty in studying natural and anthropogenic causes of climate change.

Download or read book The Role of Nonliving Organic Matter in the Earth s Carbon Cycle written by Richard G. Zepp and published by John Wiley & Sons. This book was released on 1995-07-11 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonliving organic matter (NLOM) comprises the bulk of the organic carbon stored in the terrestrial biosphere and a major part of the organic carbon in the sea. Organic substances, which include litter, marine detritus, dissolved organic matter, and soil organic matter, have diverse effects on the Earth's biogeochemical processes and serve as a major reservoir of biospheric carbon, which can be transformed to carbon dioxide, methane, and other "greenhouse" gases. Given this broad spectrum of effects, efforts to adapt to or perhaps benefit from global change require a better understanding and an ability to predict the role of NLOM in the global environment. The overall objective of this volume is to provide experimental and modeling strategies for the assessment of the sensitivity of the global carbon cycle to changes in nonliving organic pools in terrestrial and aquatic ecosystems. The discussions in this volume consider how best to characterize and quantify pools and fluxes of NLOM, the role of NLOM cycling on a global scale, human and climatic perturbations of interactions between NLOM and nutrients, and biological, chemical, and physical processes that control the production and degradation of NLOM, with an emphasis on processes that affect the persistence of NLOM in the environment. One of the most unique aspects of this volume is that it represents extensive exchanges between leading international scientists from both aquatic and terrestrial backgrounds. It will be of particular interest to organic geochemists, microbiologists, ecologists, soil scientists, agricultural scientists, marine chemists, limnologists, and modelers. Goal of this Dahlem Workshop: to devise experimental and modeling strategies for assessment of the sensitivity of the global carbon cycle to changes in nonliving organic pools.

Download or read book Optical Closure for an Aerosol Column written by Ulrich Schumann and published by . This book was released on 2001 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Earth Data Analytics for Planetary Health written by Tzai-Hung Wen and published by Springer Nature. This book was released on 2023-01-25 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Planetary health involves complex spatial–temporal interactions among agents, hosts, and earth environment. Due to rapid technical development of geomatics, including geographic information systems (GIS) and remote sensing (RS) in the era of big data analytics, therefore, earth data analytics has become one of the important approaches for monitoring earth surface process and measuring of the effects of environment changes on all humans and other living organisms on earth. Various methods in earth data analytics, including spatial–temporal statistics, spatial evolutionary algorithms, remote sensing image analysis, wireless geo-sensors, and location-based analytics, are an emerging discipline in understanding complex interactions in planetary health. This edited book provides a broad focus on methodological theories of earth data analytics and their applications to measuring the process of planetary health, with the goal to build scientific understanding on how geospatial analytics can provide valuable insights in measuring environmental risks in Southeast Asian regions. It is collection of selected papers covering both theoretical and empirical studies focusing on topics relevant to spatial perspectives on planetary health and environmental exposure studies. The book is written for senior undergraduates, graduate students, lecturers, and researchers in applications of geospatial technologies for public health and environmental studies.

Download or read book Biomass Burning in Amazonia written by John Edward Ten Hoeve (#suffix.) and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomass burning is the largest source of anthropogenic aerosols in the Southern Hemisphere. In the Amazon Basin, burning is used to clear forests, remove crop residue, and mobilize nutrients. Over the last decade, trends in biomass burning over forest and savanna/agricultural lands in the Amazon have changed dramatically. We find that between the early 2000s and the late 2000s, the ratio of forest to savanna/agricultural fires more than halved over South America, in turn changing the optical properties of aerosols in the region. This change from forest to savanna burning is attributed in part to better forest fire management, changing agricultural practices along the Amazon frontier, and reduced deforestation rates. Interannual precipitation variability over forest and savanna lands is also shown to play an important role. Biomass burning aerosols over the Amazon have a substantial effect on cloud properties and the regional radiative balance. Remote sensing observations of aerosols and clouds over Brazil illustrate that meteorological variability and aerosol-cloud overlap, ignored in previous studies, must be accounted for to correctly determine aerosol-cloud interactions from satellite observations. When accounting for these confounding variables, we find that microphysical aerosol effects, which serve to increase cloud cover and optical thickness, dominate for low levels of aerosol loading (aerosol optical depth (AOD) 0.3-0.5), whereas radiative effects, which serve to decrease cloud cover and optical thickness, dominate for higher levels of aerosol loading (AOD 0.3-0.5). We find a similar result using high-resolution nested model simulations over the Amazon Basin, which include physical representations of direct, indirect, semi-direct, and cloud absorption effects. Simulations including and excluding biomass burning emissions are used to establish causation of the remotely sensed correlations. A two-regime relationship, defined by dominance of microphysical aerosol effects at low AODs and dominance of radiative effects at high AODs, is modeled for a variety of cloud variables including cloud optical thickness, cloud liquid droplet number, cloud fraction, and precipitation. These competing effects also exhibit a strong diurnal signal -- microphysical effects dominate in the early morning whereas radiative effects dominate in the late afternoon and night. By finding consistent relationships between remotely sensed observations and modeling results, we conclude that remotely sensed correlations between aerosols and clouds are not largely dominated by retrieval artifacts such as the hygroscopic growth of aerosol particles near clouds, brightening of aerosols near clouds, darkening of clouds below absorbing aerosols, and cloud contamination of aerosol retrievals over the Amazon, and that the complex aerosol-cloud relationships determined in this and previous studies over the Amazon can be attributed to genuine physical interactions between aerosols and clouds. In the Appendix, the same 3-D modeling tools used in the Amazon biomass burning study are applied to assess the health effect from the Fukushima nuclear disaster on March 11th, 2011. Radioactive emissions for the month following the accident are determined from worldwide observations by the Comprehensive Nuclear-Test-Ban Treaty Organization. Modeled worldwide airborne concentrations are used to determine inhalation and external atmospheric exposure, modeled deposition rates are used to determine external ground-level exposure, and ingestion exposure from contaminated food and water is extrapolated from previous Chernobyl studies all assuming a linear no-threshold model of human exposure. We estimate an additional 280 (30--2400) cancer-related mortalities and 390 (50--3800) cancer-related morbidities incorporating uncertainties associated with the exposure-dose and dose-response models used in the study. A hypothetical accident at the Diablo Canyon Power Plant in California, USA, with identical emissions to Fukushima, is studied to analyze the influence of location and seasonality on the impact of a nuclear accident. This hypothetical accident may cause up to ~45% more mortalities than Fukushima despite a lower local population density due to differing meteorological conditions.

Download or read book Modeling the Spectral Optical Properties of Ammonium Sulfate and Biomass Burning Aerosols written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of including the global and regional radiative effects of aerosols in climate models has increasingly been realized. Accurate modeling of solar radiative forcing due to aerosols from anthropogenic sulfate and biomass burning emissions requires adequate spectral resolution and treatment of spatial and temporal variability. The variation of aerosol spectral optical properties with local relative humidity and dry aerosol composition must be considered. Because the cost of directly including Mie calculations within a climate model is prohibitive, parameterizations from offline calculations must be used. Starting from a log-normal size distribution of dry ammonium sulfate, we developed optical properties for tropospheric sulfate aerosol at 15 relative humidities up to 99 percent. The resulting aerosol size distributions were then used to calculate bulk optical properties at wavelengths between 0.175[micro]m and 4[micro]m. Finally, functional fits of optical properties were made for each of 12 wavelength bands as a function of relative humidity. Significant variations in optical properties occurred across the total solar spectrum. Relative increases in specific extinction and asymmetry factor with increasing relative humidity became larger at longer wavelengths. Significant variation in single-scattering albedo was found only in the longest near-IR band. This is also the band with the lowest albedo. A similar treatment was done for aerosols from biomass burning. In this case, size distributions were taken as having two carbonaceous size modes and a larger dust mode. The two carbonaceous modes were considered to be humidity dependent. Equilibrium size distributions and compositions were calculated for 15 relative humidities and five black carbon fractions. Mie calculations and Chandrasekhar averages of optical properties were done for each of the resulting 75 cases. Finally, fits were made for each of 12 spectral bands as functions of relative humidity and black carbon fraction.