Download or read book Size Distribution Chemical Composition and Optical Properties of Atmospheric Dust in Israel A Comparison of Urban and Desert Aerosols Under Clear and Dusty Conditions written by Zev Levin and published by . This book was released on 1980 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of aerosol size distributions, chemical composition and optical properties were carried out at two locations in Israel. Tel Aviv was chosen as an urban region and Mitzpe Ramon as a desert region. The measurements indicate that the size spectra between 0.15 - 12 micrometers can be approximated by a power law type distribution. The spectra in Tel Aviv show higher concentrations and greater slopes than those from the desert. Diurnal variations between day and night are observed in the size distribution of the summertime measurements in Tel Aviv. These are believed to be related to the increase in aerosol size due to absorption of water vapor during high relative humidity periods. The chemical composition in Tel Aviv was found to strongly depend on the meteorological conditions. The optical measurements also suggest strong differences between Tel Aviv and the desert. Filter samples of atmospheric particulate matter from Tel Aviv always appeared darker than those from the desert site. Measurements of imaginary refractive index in the 0.3 to 1.7 micrometer spectral region are presented. These measurements are consistently higher by a factor of 2 to 4 in Tel Aviv as compared to simultaneous samples from the desert site. Seasonal variations have also been observed and are believed to be primarily related to temperature inversions near or at the ground during the winter months and to the effect of pollution from Southern Europe which is carried eastward by synoptic scale motion.
Download or read book Size Distribution Chemical Composition and Optical Properties of Atmospheric Dust in Israel written by Zev Levin and published by . This book was released on 1980 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1980 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research in Progress Between and written by United States. Army Research Office and published by . This book was released on 1978 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research in Progress written by and published by . This book was released on 1980 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1980 with total page 1280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Current Awareness in Particle Technology written by and published by . This book was released on 1981 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1980 with total page 1428 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1980 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Aeolian Geomorphology written by Ian Livingstone and published by John Wiley & Sons. This book was released on 2019-03-18 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: A revised introduction to aeolian geomorphology written by noted experts in the field The new, revised and updated edition of Aeolian Geomorphology offers a concise and highly accessible introduction to the subject. The text covers the topics of deserts and coastlines, as well as periglacial and planetary landforms. The authors review the range of aeolian characteristics that include soil erosion and its consequences, continental scale dust storms, sand dunes and loess. Aeolian Geomorphology explores the importance of aeolian processes in the past, and the application of knowledge about aeolian geomorphology in environmental management. The new edition includes contributions from eighteen experts from four continents. All the chapters demonstrate huge advances in observation, measurement and mathematical modelling. For example, the chapter on sand seas shows the impact of greatly enhanced and accessible remote sensing and the chapter on active dunes clearly demonstrates the impact of improvements in field techniques. Other examples reveal the power of greatly improved laboratory techniques. This important text: Offers a comprehensive review of aeolian geomorphology Contains contributions from an international panel of eighteen experts in the field Includes the results of the most recent research on the topic Filled with illustrative examples that demonstrate the advances in laboratory approaches Written for students and professionals in the field, Aeolian Geomorphology provides a comprehensive introduction to the topic in twelve new chapters with contributions from noted experts in the field.
Download or read book Ocean Atmosphere Interactions of Gases and Particles written by Peter S. Liss and published by Springer. This book was released on 2013-12-18 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: The oceans and atmosphere interact through various processes, including the transfer of momentum, heat, gases and particles. In this book leading international experts come together to provide a state-of-the-art account of these exchanges and their role in the Earth-system, with particular focus on gases and particles. Chapters in the book cover: i) the ocean-atmosphere exchange of short-lived trace gases; ii) mechanisms and models of interfacial exchange (including transfer velocity parameterisations); iii) ocean-atmosphere exchange of the greenhouse gases carbon dioxide, methane and nitrous oxide; iv) ocean atmosphere exchange of particles and v) current and future data collection and synthesis efforts. The scope of the book extends to the biogeochemical responses to emitted / deposited material and interactions and feedbacks in the wider Earth-system context. This work constitutes a highly detailed synthesis and reference; of interest to higher-level university students (Masters, PhD) and researchers in ocean-atmosphere interactions and related fields (Earth-system science, marine / atmospheric biogeochemistry / climate). Production of this book was supported and funded by the EU COST Action 735 and coordinated by the International SOLAS (Surface Ocean- Lower Atmosphere Study) project office.
Download or read book Particle Flux in the Ocean written by Venugopalan Ittekkot and published by . This book was released on 1996-08-22 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle flux in the ocean is a major segment linking terrestrial, meteorological and surface ocean processes with those operating in the deep sea. This book describes how wind speeds and dust fallout over the oceans, volcanic eruptions and freshwater and suspended matter inputs from rivers influence material flux to the ocean's interior and its variability. It explores the potential use of deep ocean particle flux studies to record and monitor climatic and environmental changes.
Download or read book Principles of Environmental Physics written by John Monteith and published by Butterworth-Heinemann. This book was released on 1990-02-15 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly revised and up-dated edition of a highly successful textbook.
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.
Download or read book Desert Dust in the Global System written by Andrew S. Goudie and published by Springer Science & Business Media. This book was released on 2006-09-05 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dust storms are a vital component of the environment. This book explores and summarises recent research on where dust storms originate, why dust storms are generated, where dust is transported and deposited, the nature of dust deposits and the changing frequency of dust storms over a range of time-scales. It is the first global study of causes and effects of dust storms, which are one of the increasing nature catastrophes.
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>
