Download or read book An Improved Methodology for Characterizing Atmospheric Boundary Layer Turbulence and Dispersion written by David Fleming Brown and published by . This book was released on 1997 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Introduction to Boundary Layer Meteorology written by Roland B. Stull and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 671 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part of the excitement in boundary-layer meteorology is the challenge associated with turbulent flow - one of the unsolved problems in classical physics. An additional attraction of the filed is the rich diversity of topics and research methods that are collected under the umbrella-term of boundary-layer meteorology. The flavor of the challenges and the excitement associated with the study of the atmospheric boundary layer are captured in this textbook. Fundamental concepts and mathematics are presented prior to their use, physical interpretations of the terms in equations are given, sample data are shown, examples are solved, and exercises are included. The work should also be considered as a major reference and as a review of the literature, since it includes tables of parameterizatlons, procedures, filed experiments, useful constants, and graphs of various phenomena under a variety of conditions. It is assumed that the work will be used at the beginning graduate level for students with an undergraduate background in meteorology, but the author envisions, and has catered for, a heterogeneity in the background and experience of his readers.
Download or read book A Study of Turbulence and Dispersion in the Atmospheric Boundary Layer Above Heterogeneous Land Surfaces written by and published by . This book was released on 2000 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major objective of this study was to better understand the physical mechanisms involved in the dispersion of materials in the ABL that develops above heterogeneous land surfaces, using large eddy simulations This project consisted of three tasks: (i) An evaluation of our LES model against observations; (ii) A systematic analysis of the impact of microscale and meso-scale heat patches and topographical features on the structure of the ABL; and (iii) An analysis of the impact of these landscape heterogeneities on the dispersion of materials in the ABL. All three tasks have been fully completed. Using radiosondes, a network of surface fluxes. and a volume imaging lidar deployed in FIFE, we showed that, overall, the LES model performs quite well. However, its subgrid-scale parameterization needs to be improved to increase eddy dissipation. Various simulations using the FIFE data sets as well as ideal conditions indicate that microscale heterogeneities of surface heat fluxes and topographical features have only a minor to modest impact on the CBL, but can significantly affect the structure of turbulence. Meso-scale heterogeneities not only affect the structure of turbulence, but they can also significantly affect the mean characteristics of the CBL. These heterogeneities can also significantly affect the dispersion of materials. The results of this research were published in major peer-reviewed journals, and were presented at various professional meetings. A fourth and last year of funding was also provided to make a preliminary analysis of the ability of RAMS to simulate the stable nocturnal boundary layer (SNBL), in preparation of a more complete study on the dispersion of materials in this type of boundary layer. which will be proposed as a continuation of this completed project.
Download or read book The Atmospheric Boundary Layer written by J. R. Garratt and published by Cambridge University Press. This book was released on 1994-04-21 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book gives a comprehensive and lucid account of the science of the atmospheric boundary layer (ABL). There is an emphasis on the application of the ABL to numerical modelling of the climate. The book comprises nine chapters, several appendices (data tables, information sources, physical constants) and an extensive reference list. Chapter 1 serves as an introduction, with chapters 2 and 3 dealing with the development of mean and turbulence equations, and the many scaling laws and theories that are the cornerstone of any serious ABL treatment. Modelling of the ABL is crucially dependent for its realism on the surface boundary conditions, and chapters 4 and 5 deal with aerodynamic and energy considerations, with attention to both dry and wet land surfaces and sea. The structure of the clear-sky, thermally stratified ABL is treated in chapter 6, including the convective and stable cases over homogeneous land, the marine ABL and the internal boundary layer at the coastline. Chapter 7 then extends the discussion to the cloudy ABL. This is seen as particularly relevant, since the extensive stratocumulus regions over the subtropical oceans and stratus regions over the Arctic are now identified as key players in the climate system. Finally, chapters 8 and 9 bring much of the book's material together in a discussion of appropriate ABL and surface parameterization schemes in general circulation models of the atmosphere that are being used for climate simulation.
Download or read book Turbulence and Dispersion in the Planetary Boundary Layer written by Francesco Tampieri and published by Springer. This book was released on 2016-09-28 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a comprehensive review of our current understanding of the planetary boundary layer, particularly the turbulent exchanges of momentum, heat and passive scalars between the surface of the Earth and the atmosphere. It presents and discusses the observations and the theory of the turbulent boundary layer, both for homogeneous and more realistic heterogeneous surface conditions, as well as the dispersion of tracers. Lastly it addresses the main problems arising due to turbulence in weather, climate and atmospheric composition numerical models. Written for postgraduate and advanced undergraduate-level students and atmospheric researchers, it is also of interest to anyone wanting to understand the findings and obtain an update on problems that have yet to be solved.
Download or read book Atmospheric Boundary Layer Flows written by J. C. Kaimal and published by Oxford University Press. This book was released on 1994-01-06 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Boundary layer meteorology is the study of the physical processes that take place in the layer of air that is most influenced by the earth's underlying surface. This text/reference gives an uncomplicated view of the structure of the boundary layer, the instruments available for measuring its mean and turbulent properties, how best to make the measurements, and ways to process and analyze the data. The main applications of the book are in atmospheric modelling, wind engineering, air pollution, and agricultural meteorology. The authors have pioneered research on atmospheric turbulence and flow, and are noted for their contributions to the study of the boundary layer. This important work will interest atmospheric scientists, meteorologists, and students and faculty in these fields.
Download or read book Atmospheric Turbulence written by Hans A. Panofsky and published by Wiley-Interscience. This book was released on 1984-02-03 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: New York : Wiley, c1984.
Download or read book Turbulence in the Atmosphere written by John C. Wyngaard and published by Cambridge University Press. This book was released on 2010-01-28 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on his over forty years of research and teaching, John C. Wyngaard's textbook is an excellent up-to-date introduction to turbulence in the atmosphere and in engineering flows for advanced students, and a reference work for researchers in the atmospheric sciences. Part I introduces the concepts and equations of turbulence. It includes a rigorous introduction to the principal types of numerical modeling of turbulent flows. Part II describes turbulence in the atmospheric boundary layer. Part III covers the foundations of the statistical representation of turbulence and includes illustrative examples of stochastic problems that can be solved analytically. The book treats atmospheric and engineering turbulence in a unified way, gives clear explanation of the fundamental concepts of modeling turbulence, and has an up-to-date treatment of turbulence in the atmospheric boundary layer. Student exercises are included at the ends of chapters, and worked solutions are available online for use by course instructors.
Download or read book Dispersion by Time varying Atmospheric Boundary Layers written by Alexander Charles Taylor and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The periods of time-varying turbulence in the atmospheric boundary layer, i.e. the morning and evening transitions, are often overlooked or highly idealised by dispersion models. These transitions make up a significant portion of the diurnal cycle and are known to affect the spread of pollution due to the properties of turbulence in the residual and stable layers, resulting in phenomena such as lofting, trapping, and fumigation. Two main simulation techniques are presented for the purpose of modelling the dispersion of passive tracers in both convective and evening transitional boundary layers: Lagrangian stochastic (LS) modelling for 1D, inhomogeneous, non-stationary turbulence; and large-eddy simulation (LES) with a particle model tracing pollutant paths using a combination of the resolved flow velocities and a random displacement model to represent sub-grid scale motions. In the convective boundary layer, LS models more accurately representing the state of turbulence, and including the effect of skewness, are shown to produce dispersion results in closer agreement with LES. By considering individual particle trajectories, a reflective top boundary in LS models is shown to produce un-physical, sharp changes in velocity and position. By applying a correction to the vertical velocity variance based on representing the stable potential temperature gradient above the boundary layer, particles are contained within the boundary layer in a physically accurate way. An LS model for predicting dispersion in time-varying, skewed turbulence is developed and tested for various particle releases in transitional boundary layers with different rates of decay, showing an improvement in accuracy compared with previous LS models. Further improvement is made by applying a correction to the vertical velocity variance to represent the effect of a positive potential temperature gradient developing over the course of the transition. Finally, a developing stable boundary layer is shown to have a significant trapping effect on particles released near the surface.
Download or read book Improved Parameterization of Stably Stratified Boundary Layer Turbulence in Atmospheric Models written by and published by . This book was released on 2005 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the course of the project, our research has spanned over several areas encompassing theoretical, numerical and phenomenological aspects of stably stratified atmospheric boundary layers (SBLs). We have laid a solid foundation for studying stably stratified turbulence in the framework of a Quasi-Normal Scale Elimination theory (QNSE) developed by us. We consider the QNSE theory as a major breakthrough in this field. Being maximally proximate to the first principles, the theory penetrates very deeply into the physics of anisotropic turbulence and turbulence-wave interaction yet its calculations can be carried out analytically almost to the final results. We have performed initial analytical exploration of the new theory and implemented it in Reynolds-averaged, Navier-Stokes (RANS) models whose predictions agree well with data collected in BASE and SHEBA campaigns. In addition, we investigated non-local features of stable planetary boundary layers (PBLs) caused by semi-organized structures overlooked in traditional boundary-layer meteorology and in PBL schemes currently used in atmospheric models. Theoretical developments focused on basic length scales characterizing semi-organized structures and corresponding revision of classical similarity theory, PBL depth equations, and bulk resistance and heat/mass transfers laws.
Download or read book Turbulence Parameters for the Calculation of Dispersion in the Atmospheric Boundary Layer Parametrization of Gaussian Turbulence written by Michael J. Kerschgens and published by . This book was released on 1999 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulations of Turbulent Dispersion in the Atmospheric Boundary Layer written by Anders Andrén and published by . This book was released on 1989 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Probing the Atmospheric Boundary Layer written by Donald H. Lenschow and published by . This book was released on 1986 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulence parameters for the calculation of dispersion in the atmospheric boundary layer written by Michael Johannes Kerschgens and published by . This book was released on 1999 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamics of Atmospheric Flows written by M. P. Singh and published by Computational Mechanics. This book was released on 1998 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents: Unstable and Convective Boundary Layers; Turbulence and Dispersion in the Stable Atmospheric Boundary Layer - Sections A & B; Urban Air Pollution; Mesoscale Atmospheric Transport and Diffusion Processes; Leaky Containment Vessels of Air: A Lagrangian-Mean Approach to the Stratospheric Tracer Transport.
Download or read book Analyses of Turbulence in the Neutrally and Stably Stratified Planetary Boundary Layer written by Cedrick Ansorge and published by Springer. This book was released on 2016-09-15 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a study of strong stratification and turbulence collapse in the planetary boundary layer, opening a new avenue in this field. It is the first work to study all regimes of stratified turbulence in a unified simulation framework without a break in the paradigms for representation of turbulence. To date, advances in our understanding and the parameterization of turbulence in the stable boundary layer have been hampered by difficulties simulating the strongly stratified regime, and the analysis has primarily been based on field measurements. The content presented here changes that paradigm by demonstrating the ability of direct numerical simulation to address this problem, and by doing so to remove the uncertainty of turbulence models from the analysis. Employing a stably stratified Ekman layer as a simplified physical model of the stable boundary layer, the three stratification regimes observed in nature— weakly, intermediately and strongly stratified—are reproduced, and the data is subsequently used to answer key, long-standing questions. The main part of the book is organized in three sections, namely a comprehensive introduction, numerics, and physics. The thesis ends with a clear and concise conclusion that distills specific implications for the study of the stable boundary layer. This structure emphasizes the physical results, but at the same time gives relevance to the technical aspects of numerical schemes and post-processing tools. The selection of the relevant literature during the introduction, and its use along the work appropriately combines literature from two research communities: fluid dynamics, and boundary-layer meteorology.
Download or read book Coastal Meteorology written by National Research Council and published by National Academies Press. This book was released on 1992-02-01 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Almost half the U.S. population lives along the coast. In another 20 years this population is expected to more than double in size. The unique weather and climate of the coastal zone, circulating pollutants, altering storms, changing temperature, and moving coastal currents affect air pollution and disaster preparedness, ocean pollution, and safeguarding near-shore ecosystems. Activities in commerce, industry, transportation, freshwater supply, safety, recreation, and national defense also are affected. The research community engaged in studies of coastal meteorology in recent years has made significant advancements in describing and predicting atmospheric properties along coasts. Coastal Meteorology reviews this progress and recommends research that would increase the value and application of what is known today.
