Optical Properties of Mineral Dust Aerosol Including Analysis of Particle Size, Composition, and Shape Effects, and the Impact of Physical and Chemical Processing

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ISBN 13 :
Total Pages : 195 pages
Book Rating : 4.:/5 (925 download)

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Book Synopsis Optical Properties of Mineral Dust Aerosol Including Analysis of Particle Size, Composition, and Shape Effects, and the Impact of Physical and Chemical Processing by : Jennifer Mary Alexander

Download or read book Optical Properties of Mineral Dust Aerosol Including Analysis of Particle Size, Composition, and Shape Effects, and the Impact of Physical and Chemical Processing written by Jennifer Mary Alexander and published by . This book was released on 2015 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric mineral dust has a large impact on the earth's radiation balance and climate. The radiative effects of mineral dust depend on factors including, particle size, shape, and composition which can all be extremely complex. Mineral dust particles are typically irregular in shape and can include sharp edges, voids, and fine scale surface roughness. Particle shape can also depend on the type of mineral and can vary as a function of particle size. In addition, atmospheric mineral dust is a complex mixture of different minerals as well as other, possibly organic, components that have been mixed in while these particles are suspended in the atmosphere. Aerosol optical properties are investigated in this work, including studies of the effect of particle size, shape, and composition on the infrared (IR) extinction and visible scattering properties in order to achieve more accurate modeling methods. Studies of particle shape effects on dust optical properties for single component mineral samples of silicate clay and diatomaceous earth are carried out here first. Experimental measurements are modeled using T-matrix theory in a uniform spheroid approximation. Previous efforts to simulate the measured optical properties of silicate clay, using models that assumed particle shape was independent of particle size, have achieved only limited success. However, a model which accounts for a correlation between particle size and shape for the silicate clays offers a large improvement over earlier modeling approaches. Diatomaceous earth is also studied as an example of a single component mineral dust aerosol with extreme particle shapes. A particle shape distribution, determined by fitting the experimental IR extinction data, used as a basis for modeling the visible light scattering properties.

Physicochemical Properties of Mineral Dust and Sea Spray Aerosols

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ISBN 13 :
Total Pages : 321 pages
Book Rating : 4.:/5 (918 download)

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Book Synopsis Physicochemical Properties of Mineral Dust and Sea Spray Aerosols by : Olga Laskina

Download or read book Physicochemical Properties of Mineral Dust and Sea Spray Aerosols written by Olga Laskina and published by . This book was released on 2015 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerosols are important atmospheric constituents that impact the Earth's radiative balance and climate. The detailed knowledge of the aerosol optical properties is required for a comprehensive analysis of the impacts of aerosols on climate. Mie theory is often used in satellite and ground-based retrieval algorithms to account for atmospheric mineral dust. However, the approximations used in Mie theory are often not appropriate for mineral dust and can lead to errors in the optical properties modeling. Analytic models based on Rayleigh theory that account for particle shapes can offer significant advantages when used to model infrared (IR) extinction of mineral dust. Here, the IR optical properties of some components of mineral dust, authentic dust samples and minerals processed with organic acids were investigated. Detailed characterization of the particles through online and offline methods of analysis that include IR extinction spectroscopy, micro-Raman spectroscopy and scanning electron microscopy was performed. Analysis of the IR extinction spectra and spectral simulations showed that the positions of the peaks and the shapes of the bands of the IR characteristic features are not well simulated by Mie theory in any of the samples studied. The resonance peaks were consistently shifted relative to the experimental spectrum in the Mie simulation. Rayleigh model solutions derived for different particle shapes better predicted the peak positions and band shapes of experimental spectra. To fill the gaps in the refractive index data for atmospherically relevant organic compounds in the IR region optical properties of atmospherically relevant carboxylic acids and humic-like substances using the IR extinction spectra and size distributions measured in the laboratory were determined. In addition to properties of mineral dust this dissertation focuses on properties of sea spray aerosol. Chemical and elemental composition of individual sea spray aerosol particles were studies using micro-Raman spectroscopy, mass-spectrometry and X-ray spectroscopy to provide insights into the biochemical processes that give rise to classes of organic molecules that make up these aerosol particles. The results suggested that degradation of biota (bacteria and diatoms) present in sea water led to lipopolysaccharides and extracellular polymeric substances that further degraded down to carbohydrates and fatty acids. Solubility of the resulting organic species seemed to play a role in their transfer to the aerosol phase. Furthermore, water uptake and hygroscopic growth of multi-component particles were studied. Understanding the interactions of water with atmospheric aerosols is crucial for determining their size, physical state, reactivity, and therefore for aerosol interactions with electromagnetic radiation and clouds. It was determined that particles composed of ammonium sulfate with succinic acid and of mixture of chlorides typical for marine environment show size dependent hygroscopic behavior. Microscopic analysis of the distribution of components within the aerosol particles showed that the observed size dependence is due to the differences in the mixing state. The composition and water uptake properties of sea spray aerosol particles were also measured during a phytoplankton bloom. The results showed that water uptake properties were directly related to the chemical composition of the particles and hygroscopicity decreased with increase in the fraction of water insoluble organic matter emitted during phytoplankton bloom. Finally, multiple methods of particle size, phase and shape analysis were compared and the results showed that the techniques that operate under ambient conditions provide the most relevant and robust measurement of particle size. Additionally, several storage methods for substrate deposited aerosol particles were evaluated and it was determined that storing samples at low relative humidity led to irreversible changes due to sample dehydration while sample freezing and thawing leads to irreversible changes due to phase changes and water condensation. Therefore it is suggested that samples used for single-particles analysis should be stored at ambient laboratory conditions, or near conditions which they were collected, in order to preserve the sample phase and hydration state. The results presented in this dissertation provide insight into physicochemical properties of atmospheric aerosols and help us better understand the role of aerosol particles in the Earth's atmosphere.

Morphology and Optical Properties of Aerosol Particles

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Total Pages : pages
Book Rating : 4.:/5 (915 download)

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Book Synopsis Morphology and Optical Properties of Aerosol Particles by : Daniel Veghte

Download or read book Morphology and Optical Properties of Aerosol Particles written by Daniel Veghte and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Major factors that affect climate change depend on gas and particulate phase components in the atmosphere. Gas phase species have been studied in great detail and are well understood, causing a warming effect on the atmosphere. The less understood major contributing factor in the atmosphere are aerosol particles, which range in size from nanometers up to microns. Aerosol particles can directly scatter and absorb light and also have secondary effects such as acting as a surface for gas phase reactions to occur or seed particles for cloud formation. Aerosol particles can cause health problems ranging from serious cardiovascular to respiratory effects. All Climate and health effects of aerosol particles are dependent on particle composition, morphology, concentration, and size. Since a large variety of particulate types exist in the atmosphere, we have focused on understanding the effect of mineral dust composition and morphology. Mineral dust is important because it is the second largest emission by mass. In order to study the optical properties of aerosol particles, we built a cavity ring-down spectrometer and developed methods to interpret the excinction cross section results for particles with a varied shape. We have studied the major components of mineral dust that include calcium carbonate, hematite, quartz, aluminosilicate clay minerals, and feldspars, along with a heterogeneous dust sample. We have found that non-absorbing species that have surface roughness and an aspect ratio close to one (such as calcite, quartz and feldspar) can be treated as spheres. Aerosol particles that are absorbing (hematite) that have an aspect ratio near one with a roughened surface need to be treated with more complex models; otherwise the extinction cross section will be underrepresented. For aerosol particles that are non-absorbing but have a high aspect ratio (aluminosilicate clay minerals), additional modeling parameters are also needed that will account for shape and orientation. We have used Arizona Test Dust to determine if the models we have developed can be used to model the optical properties of a heterogeneous mixture. We have shown that the extinction cross section of the Arizona Test Dust can be modeled as long as individual components are treated independently and significant error would be introduces if all species were treated as spheres.Organic aerosol particles are chemically complex species that originate from primary or secondary emissions. We have described mixed organic/ammonium sulfate particles in the submicron regime using TEM to understand phase separation. When the organic component has a high aqueous solubility, all particles exhibit a homogeneous morphology while at low aqueous solubility all particles exhibit a phase separated structure. Intermediate solubility organics show a size dependent morphology. For pimelic and succinic acid, small particles (under approximately 200 nm) have a homogeneous structure while the larger particles exhibit phase separated structures. We have studied samples collected in Ulaanbaatar, Mongolia to better understand the types of particles and the effect of aging on these particles in an urban environment. The majority of the particles are soot, small spheres, or mineral dust. When we compared the monthly particle composition, we saw that there was an increased aging of the particles during the winter months due to pollution and a lower boundary layer leading to reduced atmospheric mixing. By understanding the particle composition present in areas and modeling the optical properties of individual particle types, better models can be created to give insight into aerosol particles affects on the atmosphere.

Sensitivity Study of the Effects of Mineral Dust Particle Nonsphericity and Thin Cirrus Clouds on Modis Dust Optical Depth Retrievals and Direct Radiative Forcing Calculations

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Book Synopsis Sensitivity Study of the Effects of Mineral Dust Particle Nonsphericity and Thin Cirrus Clouds on Modis Dust Optical Depth Retrievals and Direct Radiative Forcing Calculations by : Qian Feng

Download or read book Sensitivity Study of the Effects of Mineral Dust Particle Nonsphericity and Thin Cirrus Clouds on Modis Dust Optical Depth Retrievals and Direct Radiative Forcing Calculations written by Qian Feng and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A special challenge posed by mineral dust aerosols is associated with their predominantly nonspherical particle shapes. In the present study, the scattering and radiative properties for nonspherical mineral dust aerosols at violet-to-blue (0.412, 0.441, and 0.470 [mu]m) and red (0.650 [mu]m) wavelengths are investigated. To account for the effect of particle nonsphericity on the optical properties of dust aerosols, the particle shapes for these particles are assumed to be spheroids. A combination of the T-matrix method and an improved geometric optics method is applied to the computation of the single-scattering properties of spheroidal particles with size parameters ranging from the Rayleigh to geometric optics regimes. For comparison, the Mie theory is employed to compute the optical properties of spherical dust particles that have the same volumes as their nonspherical counterparts. The differences between the phase functions of spheroidal and spherical particles lead to quite different lookup tables (LUTs) involved in retrieving dust aerosol properties. Moreover, the applicability of a hybrid approach based on the spheroid model for the phase function and the sphere model for the other phase matrix elements is demonstrated. The present sensitivity study, employing the Moderate Resolution Imaging Spectroradiometer (MODIS) observations and the fundamental principle of the Deep Blue algorithm, illustrates that neglecting the nonsphericity of dust particles leads to an underestimate of retrieved aerosol optical depth at most scattering angles, and an overestimate is noted in some cases. The sensitivity study of the effect of thin cirrus clouds on dust optical depth retrievals is also investigated and quantified from MODIS observations. The importance of identifying thin cirrus clouds in dust optical depth retrievals is demonstrated. This has been undertaken through the comparison of retrieved dust optical depths by using two different LUTs. One is for the dust only atmosphere, and the other is for the atmosphere with overlapping mineral dust and thin cirrus clouds. For simplicity, the optical depth and bulk scattering properties of thin cirrus clouds are prescribed a priori. Under heavy dusty conditions, the errors in the retrieved dust optical depths due to the effect of thin cirrus are comparable to the assumed optical depth of thin cirrus clouds. With the spheroidal and spherical particle shape assumptions for mineral dust aerosols, the effect of particle shapes on dust radiative forcing calculations is estimated based on Fu-Liou radiative transfer model. The effect of particle shapes on dust radiative forcing is illustrated in the following two aspects. First, the effect of particle shapes on the single-scattering properties of dust aerosols and associated dust direct radiative forcing is assessed, without considering the effect on dust optical depth retrievals. Second, the effect of particle shapes on dust direct radiative forcing is further discussed by including the effect of particle nonsphericity on dust optical depth retrievals.

Optical Effects Associated with Small Particles

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Publisher : World Scientific
ISBN 13 : 9789971504625
Total Pages : 362 pages
Book Rating : 4.5/5 (46 download)

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Book Synopsis Optical Effects Associated with Small Particles by : Peter W. Barber

Download or read book Optical Effects Associated with Small Particles written by Peter W. Barber and published by World Scientific. This book was released on 1988 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is a collection of review articles by scientists who have pioneered many of the recent advances in studies of the optical effects of small particles. The book begins with a review of the multitude of sharp dielectric resonances which exist in all optical spectra as a result of particle size and shape. Latest advances in absorption and fluorescence spectroscopy of a single particle and/or an ensemble of particles are also discussed, as well as advances in the energy transfer mechanisms for molecules embedded in the particle. The effects of laser-induced heating on a single particle are reviewed in terms of the hydrodynamics and thermodynamics of the liquid droplet and its ambient gas surrounding. The limits of applying bulk optical constants to small particles which lie between the bulk substance and the quantum-sized substance are also presented.

Study of the Variability and Impact on Optical Properties Calculation of Mineral Dust Aerosols

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (122 download)

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Book Synopsis Study of the Variability and Impact on Optical Properties Calculation of Mineral Dust Aerosols by : Alejandra Vicaría Aguilar

Download or read book Study of the Variability and Impact on Optical Properties Calculation of Mineral Dust Aerosols written by Alejandra Vicaría Aguilar and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiative forcing on the atmosphere due to mineral dust aerosols plays a key role in climate change. This results from dust optical properties, more specifically the Single Scattering Albedo (SSA), which is a key aerosol optical parameter and determines sign and magnitude of radiative forcing due to aerosols. In order to get a better understanding of how mineral dust aerosols have an impact on climate, it is of great importance the study of the variability of the mineralogical composition of airborne dust. Here, we revise two data sets that provide mineralogical information for several soil units of the clay and the silt fraction of the soil based on the relative abundance of selected minerals. Furthermore, this paper is focused on the study of the variability of the relative abundance of iron oxide minerals and mean iron content of soils, which are key to determine the SSA of mineral dust in the short-wave spectrum. A regional analysis is conducted in the Sahara desert, located in northern Africa, to study the variability in the relative abundance of hematite and goethite according to each data set. These analyses are conducted by statistical analyses and developing adequate MATLAB codes in order to obtain the desired results. Results show a high variability and large uncertainties on the definition of iron oxide minerals in the erodible fraction of the soil, presenting high coefficients of variance for both data sets. This uncertainty on the resulting values is due to lack of mineralogical data and hypothesis that have been assumed in order to provide more geographical coverage. Mineralogical maps in a 0.5' x 0.5' grid, have been constructed from data extracted from the databases in order to display geographical distribution of the mineralogical composition at a global or regional scale. Finally, the SSA of mineral dust, at two wavelengths 405 nm and 870 nm, basing the calculations on the linear relationship established in Moosmüller et al. (2012), that relates the iron content to the SSA. This optical parameter calculated for 12 textural soil classes and for the region of the Sahara desert. Results present a high SSA in both case analyses, but when calculating the SSA for the Sahara region, the SSA is relatively higher to those presented in the theoretical calculations for the soil textural classes. Nevertheless, as we obtain a high values, as expected, it is confirmed that iron content in mineral dust affects significantly the values of the Single Scattering Albedo.

Light Scattering by Ice Crystals and Mineral Dust Aerosols in the Atmosphere

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (85 download)

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Book Synopsis Light Scattering by Ice Crystals and Mineral Dust Aerosols in the Atmosphere by : Lei Bi

Download or read book Light Scattering by Ice Crystals and Mineral Dust Aerosols in the Atmosphere written by Lei Bi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling the single-scattering properties of nonspherical particles in the atmosphere (in particular, ice crystals and dust aerosols) has important applications to climate and remote sensing studies. The first part of the dissertation (Chapters II-V) reports a combination of exact numerical methods, including the finite-difference time-domain (FDTD), the discrete-dipole-approximation (DDA), and the T-matrix methods, and an approximate method-the physical-geometric optics hybrid (PGOH) method-in the computation of the optical properties of the non-spherical particles in a complete range of size parameters. The major advancements are made on the modeling capabilities of the PGOH method, and the knowledge of the electromagnetic tunneling effect -- a semi-classical scattering effect. This research is important to obtain reliable optical properties of nonspherical particles in a complete range of size parameters with satisfactory accuracy and computational efficiency. The second part (Chapters VI-VII) of the dissertation is to investigate the dependence of the optical properties of ice crystals and mineral dust aerosols in the atmosphere on the spectrum, the particle size and the morphology based on computational models. Ice crystals in the atmosphere can be classified to be simple regular faceted particles (such as hexagon columns, plates, etc.) and imperfect ice crystals. Modeling of the scattering by regular ice crystals is straightforward, as their morphologies can be easily defined. For imperfect ice crystals, the morphology is quite diverse, which complicates the modeling process. We present an effective approach of using irregular faceted particle to characterize the imperfectness of ice crystals. As an example of application, less-than-unity backscattering color ratio of cirrus clouds is demonstrated and explained theoretically, which provides guidance in the calibration algorithm for 1.064-[mu]m channel on the Calipso lidar. Dust aerosols have no particular morphology. To develop an approach to modeling the optical properties of realistic dust particles, the principle of using simple shapes (triaxial ellipsoids and nonsymmetric hexahedra) to represent irregular dust particles is explored. Simulated results have been compared with those measured in laboratory for several realistic aerosol samples. Agreement between simulated results and measurement suggests the potential applicability of the two aforementioned aerosol models. We also show the potential impact of the present study to passive and active atmospheric remote sensing and future research works.

The Impact of Desert Dust Across the Mediterranean

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Publisher : Springer Science & Business Media
ISBN 13 : 0792342941
Total Pages : 415 pages
Book Rating : 4.7/5 (923 download)

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Book Synopsis The Impact of Desert Dust Across the Mediterranean by : Stefano Guerzoni

Download or read book The Impact of Desert Dust Across the Mediterranean written by Stefano Guerzoni and published by Springer Science & Business Media. This book was released on 1996-11-30 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: The atmosphere is an important pathway for the transport of continentally-derived material to the oceans. In this respect the Mediterranean Sea is of special importance because its atmosphere receives inputs of anthropogenic aerosols from the north and desert- derived Saharan dusts from the south. The dusts, much of which is transported in the form of seasonal `pulses', have important effects on climate, marine chemistry and sedimentation in the Mediterranean Sea. This volume brings together reviews and specific-topic papers on the following aspects of Saharan dust transport to the Mediterranean Sea: (i) the modelling of Saharan dust transport, (ii) the chemistry and mineralogy of the dusts and their effect on precipitation, (iii) the contribution of the dusts to marine sedimentation, (iv) the aerobiology of the dusts, and (v) climatic implications of Saharan dust transport. The volume is aimed at students and researchers with an interest in the climate, biogeochemistry and geology of the Mediterranean Sea.

Scattering, Absorption, and Emission of Light by Small Particles

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Publisher : Cambridge University Press
ISBN 13 : 9780521782524
Total Pages : 562 pages
Book Rating : 4.7/5 (825 download)

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Book Synopsis Scattering, Absorption, and Emission of Light by Small Particles by : Michael I. Mishchenko

Download or read book Scattering, Absorption, and Emission of Light by Small Particles written by Michael I. Mishchenko and published by Cambridge University Press. This book was released on 2002-06-06 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thorough and up-to-date treatment of electromagnetic scattering by small particles.

The Soils of Iceland

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Publisher : Springer
ISBN 13 : 9401796211
Total Pages : 193 pages
Book Rating : 4.4/5 (17 download)

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Book Synopsis The Soils of Iceland by : Olafur Arnalds

Download or read book The Soils of Iceland written by Olafur Arnalds and published by Springer. This book was released on 2015-01-06 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this new volume in the World Soil series, the various types of Icelandic soils, their different characteristics, their formation, degradation and erosion are reviewed. At the same time, the book also deals with the agriculture and land use in general to give a complete view of Icelandic soils. The first part details the natural parameters such as the climate and the geography of Iceland. It also explains Icelandic geology, which is the major parameter controlling the soil formation in this country. The author describes the formation of Iceland, the main volcanic systems, central volcanoes, tephra production and its influence on the soils. Explanations on rocks, glaciers, rivers and other main geologic features are also given. The book continues with a description of the Icelandic geomorphology, giving insights on the main surface types, frost, cryoturbation and other cryogenic features. Then it details the different types of soils, their formation and main features, comparing the Icelandic soils to other soils elsewhere in the world. Erosion and land degradation are then reviewed, including the exceptionally active wind erosion and dust production. Finally, it gives an insight on land use, agriculture and vegetation types. All this accompanied by the most amazing photos to illustrate the great diversity of Icelandic Soil.

Measurements of the Chemical, Physical, and Optical Properties of Single Aerosol Particles

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ISBN 13 :
Total Pages : 340 pages
Book Rating : 4.:/5 (758 download)

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Book Synopsis Measurements of the Chemical, Physical, and Optical Properties of Single Aerosol Particles by : Ryan Christopher Moffet

Download or read book Measurements of the Chemical, Physical, and Optical Properties of Single Aerosol Particles written by Ryan Christopher Moffet and published by . This book was released on 2007 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge of aerosol physical, chemical, optical properties is essential for judging the effect that particulates have on human health, climate and visibility. The aerosol time-of-flight mass spectrometer (ATOFMS) is capable of measuring, in real-time, the size and chemical composition of atmospheric aerosols. This was exemplified by the recent deployments of the ATOFMS to Mexico City and Riverside. The ATOFMS provided rapid information about the major particle types present in the atmosphere. Industrial sources of particles, such as fine mode particles containing lead, zinc and chloride were detected in Mexico City. The rapid time response of the ATOFMS was also exploited to characterize a coarse particle concentrator used in human health effects studies. The ATOFMS showed the ability to detect changes in particle composition with a time resolution of 15 min during short 2 hour human exposure studies.

Investigation of Mineral Dust Aerosols - Chemistry Intractions in the Marine Environments

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (252 download)

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Book Synopsis Investigation of Mineral Dust Aerosols - Chemistry Intractions in the Marine Environments by : Gill-Ran Jeong

Download or read book Investigation of Mineral Dust Aerosols - Chemistry Intractions in the Marine Environments written by Gill-Ran Jeong and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Mineral dust aerosols play an important role in atmospheric chemistry through photolysis and heterogeneous uptake. Both mechanisms strongly depend on the size and composition of mineral dust. Because of the complex nature of dust, chemistry modeling commonly relies on simplified assumptions about the properties of dust particles relevant to physiochemical processes. The goal of this thesis is to investigate the impact of size-resolved composition of dust aerosols on atmospheric photochemistry. The relative importance of dust characteristics in photolysis and heterogeneous loss and the relative roles of the two mechanisms on atmospheric photochemistry are investigated. A new block of spectral aerosol optical properties was developed and incorporated into the tropospheric ultraviolet and visible radiation transfer code in order to calculate spectral actinic fluxes and photolysis rates, J-values. The Fuchs-Sutugin approximation was employed to compute mass transfer from gas to dust mineral species and heterogeneous loss rate, kloss, j. The J-values and kloss, j were incorporated into a one-dimensional photochemistry model to simulate the diurnal cycle of a vertical profile of photochemical species. Several cases of dust loading were considered in the clean and polluted marine environments. A size-resolved mineralogical composition was constructed by selecting a range of the mass fraction of the three main mineral species such as iron oxide-containing clay minerals, carbonate-containing species, and quartz.

Atmospheric Chemistry and Physics

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Publisher : John Wiley & Sons
ISBN 13 : 1118591364
Total Pages : 1249 pages
Book Rating : 4.1/5 (185 download)

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Book Synopsis Atmospheric Chemistry and Physics by : John H. Seinfeld

Download or read book Atmospheric Chemistry and Physics written by John H. Seinfeld and published by John Wiley & Sons. This book was released on 2012-12-18 with total page 1249 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly restructured and updated with new findings and new features The Second Edition of this internationally acclaimed text presents the latest developments in atmospheric science. It continues to be the premier text for both a rigorous and a complete treatment of the chemistry of the atmosphere, covering such pivotal topics as: * Chemistry of the stratosphere and troposphere * Formation, growth, dynamics, and properties of aerosols * Meteorology of air pollution * Transport, diffusion, and removal of species in the atmosphere * Formation and chemistry of clouds * Interaction of atmospheric chemistry and climate * Radiative and climatic effects of gases and particles * Formulation of mathematical chemical/transport models of the atmosphere All chapters develop results based on fundamental principles, enabling the reader to build a solid understanding of the science underlying atmospheric processes. Among the new material are three new chapters: Atmospheric Radiation and Photochemistry, General Circulation of the Atmosphere, and Global Cycles. In addition, the chapters Stratospheric Chemistry, Tropospheric Chemistry, and Organic Atmospheric Aerosols have been rewritten to reflect the latest findings. Readers familiar with the First Edition will discover a text with new structures and new features that greatly aid learning. Many examples are set off in the text to help readers work through the application of concepts. Advanced material has been moved to appendices. Finally, many new problems, coded by degree of difficulty, have been added. A solutions manual is available. Thoroughly updated and restructured, the Second Edition of Atmospheric Chemistry and Physics is an ideal textbook for upper-level undergraduate and graduate students, as well as a reference for researchers in environmental engineering, meteorology, chemistry, and the atmospheric sciences. Click here to Download the Solutions Manual for Academic Adopters: http://www.wiley.com/WileyCDA/Section/id-292291.html

Investigation of the Optical and Cloud Forming Properties of Pollution, Biomass Burning, and Mineral Dust Aerosols

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (811 download)

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Book Synopsis Investigation of the Optical and Cloud Forming Properties of Pollution, Biomass Burning, and Mineral Dust Aerosols by : Yong Seob Lee

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.

Mineral Dust

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Publisher : Springer
ISBN 13 : 9401789789
Total Pages : 526 pages
Book Rating : 4.4/5 (17 download)

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Book Synopsis Mineral Dust by : Peter Knippertz

Download or read book Mineral Dust written by Peter Knippertz and published by Springer. This book was released on 2014-09-01 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents state-of-the-art research about mineral dust, including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies. Dust research is a new, dynamic and fast-growing area of science and due to its multiple roles in the Earth system, dust has become a fascinating topic for many scientific disciplines. Aspects of dust research covered in this book reach from timescales of minutes (as with dust devils, cloud processes and radiation) to millennia (as with loess formation and oceanic sediments), making dust both a player and recorder of environmental change. The book is structured in four main parts that explore characteristics of dust, the global dust cycle, impacts of dust on the Earth system, and dust as a climate indicator. The chapters in these parts provide a comprehensive, detailed overview of this highly interdisciplinary subject. The contributions presented here cover dust from source to sink and describe all the processes dust particles undergo while travelling through the atmosphere. Chapters explore how dust is lifted and transported, how it affects radiation, clouds, regional circulations, precipitation and chemical processes in the atmosphere and how it deteriorates air quality. The book explores how dust is removed from the atmosphere by gravitational settling, turbulence or precipitation, how iron contained in dust fertilizes terrestrial and marine ecosystems, and about the role that dust plays in human health. We learn how dust is observed, simulated using computer models and forecast. The book also details the role of dust deposits for climate reconstructions. Scientific observations and results are presented, along with numerous illustrations. This work has an interdisciplinary appeal and will engage scholars in geology, geography, chemistry, meteorology and physics, amongst others with an interest in the Earth system and environmental change. body>

Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies

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Publisher :
ISBN 13 :
Total Pages : pages
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Book Synopsis Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies by : Bingqi Yi

Download or read book Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies written by Bingqi Yi and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation aims to study the broadband optical properties and radiative effects of dust aerosols and ice clouds. It covers three main topics: the uncertainty of dust optical properties and radiative effects from the dust particle shape and refractive index, the influence of ice particle surface roughening on the global cloud radiative effect, and the simulations of the global contrail radiative forcing. In the first part of this dissertation, the effects of dust non-spherical shape on radiative transfer simulations are investigated. We utilize a spectral database of the single-scattering properties of tri-axial ellipsoidal dust-like aerosols and determined a suitable dust shape model. The radiance and flux differences between the spherical and ellipsoidal models are quantified, and the non-spherical effect on the net flux and heating rate is obtained over the solar spectrum. The results indicate the particle shape effect is related to the dust optical depth and surface albedo. Under certain conditions, the dust particle shape effect contributes to 30% of the net flux at the top of the atmosphere. The second part discusses how the ice surface roughening can exert influence on the global cloud radiative effect. A new broadband parameterization for ice cloud bulk scattering properties is developed using severely roughened ice particles. The effect of ice particle surface roughness is derived through simulations with the Fu-Liou and RRTMG radiative transfer codes and the Community Atmospheric Model. The global averaged net cloud radiative effect due to surface roughness is around 1.46 Wm-2. Non-negligible increase in longwave cloud radiative effect is also found. The third part is about the simulation of global contrail radiative forcing and its sensitivity studies using both offline and online modeling frameworks. Global contrail distributions from the literature and Contrail Cirrus Prediction Tool are used. The 2006 global annual averaged contrail net radiative forcing from the offline model is estimated to be 11.3 mW m^(-2), with the regional contrail radiative forcing being more than ten times stronger. Sensitivity tests show that contrail effective size, contrail layer height, the model cloud overlap assumption, and contrail optical properties are among the most important factors. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/151136

Aerosol Optical Properties

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ISBN 13 :
Total Pages : 350 pages
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Book Synopsis Aerosol Optical Properties by : Mariya M. Shcherbyna

Download or read book Aerosol Optical Properties written by Mariya M. Shcherbyna and published by . This book was released on 2006 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: