Download or read book Marine Boundary Layer Parameterizations for Large Scale Models Data Analysis and Verification written by and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The data sampling and analysis techniques associated with research under this AASERT grant will aid in better estimates of fluxes from observations, a requirement for model verification. The new analysis techniques allow decomposition of the flow into localized modes which are more natural to boundary layer problems compared to the usual Fourier decomposition. The analysis techniques are applicable to observational data sets as well as numerical output. The usual assumption of alignment of the surface stress and surface wind vector was reexamined. This assumption appears to break down with significant temperature advection. This problem was examined in terms of tower data collected in the coastal zone by the Risoe National Laboratory (Denmark). The usual formulation of the surface heat flux in models is inconsistent in that the aerodynamic temperature required for Monin-Okukhov similarity theory is replaced by the surface radiation temperature. The aerodynamic temperature is not readily available and numerous empirical fixes have been suggested to dose the system. The approach here documents these problems by relating the evaporative fraction to remotely sensed information using data from the Boreal Ecosystem-Atmosphere Study and the California Ozone Deposition Experiment.

Download or read book Marine Boundary Layer Parameterizations for Large Scale Models Data Analysis and Verification AASERT written by and published by . This book was released on 1996 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The data sampling and analysis techniques associated with research under this AASERT grant will aid in better estimates of fluxes from observations, a requirement for model verification. The new analysis techniques allow decomposition of the flow into localized modes which are more natural to boundary layer problems compared to the usual Fourier decomposition. The analysis techniques are applicable to observational data sets as well as numerical output. The usual assumption of alignment of the surface stress and surface wind vector was reexamined. This assumption appears to break down with significant temperature advection. This problem was examined in terms of tower data collected in the coastal zone by the Risoe National Laboratory (Denmark). The usual formulation of the surface heat flux in models is inconsistent in that the aerodynamic temperature required for Monin-Okukhov similarity theory is replaced by the surface radiation temperature. The aerodynamic temperature is not readily available and numerous empirical fixes have been suggested to dose the system. The approach here documents these problems by relating the evaporative fraction to remotely sensed information using data from the Boreal Ecosystem-Atmosphere Study and the California Ozone Deposition Experiment.

Download or read book Ocean Modeling and Parameterization written by Eric P. Chassignet and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: The realism of large scale numerical ocean models has improved dra matically in recent years, in part because modern computers permit a more faithful representation of the differential equations by their algebraic analogs. Equally significant, if not more so, has been the improved under standing of physical processes on space and time scales smaller than those that can be represented in such models. Today, some of the most challeng ing issues remaining in ocean modeling are associated with parameterizing the effects of these high-frequency, small-space scale processes. Accurate parameterizations are especially needed in long term integrations of coarse resolution ocean models that are designed to understand the ocean vari ability within the climate system on seasonal to decadal time scales. Traditionally, parameterizations of subgrid-scale, high-frequency mo tions in ocean modeling have been based on simple formulations, such as the Reynolds decomposition with constant diffusivity values. Until recently, modelers were concerned with first order issues such as a correct represen tation of the basic features of the ocean circulation. As the numerical simu lations become better and less dependent on the discretization choices, the focus is turning to the physics of the needed parameterizations and their numerical implementation. At the present time, the success of any large scale numerical simulation is directly dependent upon the choices that are made for the parameterization of various subgrid processes.

Download or read book Marine Boundary Layer Parameterizations for Large Scale Models written by L. Mahrt and published by . This book was released on 1994 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes work on the PL atmospheric boundary-layer model conducted under contract number F19628-91-K-0002 from the Phillips Laboratory. This model was developed to provide turbulence parameterization schemes for a global numerical weather prediction model. In this report, boundary-layer nonlocal turbulent mixing is reexamined, and a nonlocal momentum mixing formulation is presented. The boundary-layer cloud formulation, that accounts for turbulent and subgrid-mesoscale moisture variations, is extended to include enhanced cloud mixing using moist conservative variables. Observational data and results from model simulations are used to examine the complex land-surface/atmosphere interactions and the potential for cloud development. Exchange coefficients for subgrid fluxes are shown to depend significantly on grid size in the presence mesoscale motion induced by surface heterogeneity. Tower and aircraft-measured fluxes over heterogeneous terrain are analyzed to show the spatial variation of surface fluxes and the effect on the surface exchange coefficients for area-averaged fluxes. The classical bulk aerodynamic method for estimating surface fluxes in terms of surface radiative temperature is examined. A new sea-surface roughness formulation includes the effects of aerodynamically smooth and rough flow, and wave age in terms of a simple wind tendency relation. Subgrid variability, Atmospheric boundary-layer, Surface fluxes, Boundary-layer model, Surface energy balance, Cloud cover parameterization, Ocean surface roughness.

Download or read book Parameterization Schemes written by David J. Stensrud and published by Cambridge University Press. This book was released on 2007-05-03 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents: 1.

Download or read book Boundary Layer Dynamics written by National Research Council and published by National Academies Press. This book was released on 1997-04-24 with total page 49 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 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Data Models and Analysis written by Guoqi Han and published by Routledge. This book was released on 2019-07-09 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the ten most cited articles that have appeared in the journal Atmosphere-Ocean since 1995. These articles cover a wide range of topics in meteorology, climatology and oceanography. Modelling work is represented in five papers, covering global climate model development; a cumulus parameterization scheme for global climate models; development of a regional forecast modelling system and parameterization of peatland hydraulic processes for climate models. Data rehabilitation and compilation in order to support trend analysis work on comprehensive precipitation and temperature data sets is presented in four papers. Field studies are represented by a paper on the circumpolar lead system. While the modelling studies are global in their application and applicability, the data analysis and field study papers cover environments that are specifically, but not uniquely, Canadian. This book will be of interest to researchers, students and professionals in the various sub-fields of meteorology, oceanography and climate science.

Download or read book Research in Progress FY 1992 written by United States. Department of Energy. Office of Health and Environmental Research and published by . This book was released on 1993 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigating Marine Boundary Layer Parameterizations by Combining Observations with Models Via State Estimation written by and published by . This book was released on 2015 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this project we have improved numerical weather prediction analyses and forecasts of low level winds in the marine boundary layer. This has been accomplished with the following tools; The National Center for Atmospheric Research (NCAR) Weather and Research Forecasting model, WRF, both in his single column (SCM) and three-dimensional (3D) versions; The National Oceanic and Atmospheric Administration (NOAA) Wave Watch III (WWIII); SE algorithms from the Data Assimilation Research Testbed (DART, Anderson et al. 2009); and Observations of key quantities of the lower MBL, including temperature and winds at multiple levels above the sea surface. The experiments with the WRF SCM / DART system have lead to large improvements with respect to a standard WRF configuration, which is currently commonly used by the wind energy industry. The single column model appears to be a tool particularly suitable for off-shore wind energy applications given its accuracy, the ability to quantify uncertainty, and the minimal computational resource requirements. In situations where the impact of an upwind wind park may be of interest in a downwind location, a 3D approach may be more suitable. We have demonstrated that with the WRF 3D / DART system the accuracy of wind predictions (and other meteorological parameters) can be improved over a 3D computational domain, and not only at specific locations. All the scripting systems developed in this project (i.e., to run WRF SCM / DART, WRF 3D / DART, and the coupling between WRF and WWIII) and the several modifications and upgrades made to the WRF SCM model will be shared with the broader community.

Download or read book Buoyant Convection in Geophysical Flows written by Erich J. Plate and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies of convection in geophysical flows constitute an advanced and rapidly developing area of research that is relevant to problems of the natural environment. During the last decade, significant progress has been achieved in the field as a result of both experimental studies and numerical modelling. This led to the principal revision of the widely held view on buoyancy-driven turbulent flows comprising an organised mean component with superimposed chaotic turbulence. An intermediate type of motion, represented by coherent structures, has been found to play a key role in geophysical boundary layers and in larger scale atmospheric and hydrospheric circulations driven by buoyant forcing. New aspects of the interaction between convective motions and rotation have recently been discovered and investigated. Extensive experimental data have also been collected on the role of convection in cloud dynamics and microphysics. New theoretical concepts and approaches have been outlined regarding scaling and parameterization of physical processes in buoyancy-driven geophysical flows. The book summarizes interdisciplinary studies of buoyancy effects in different media (atmosphere and hydrosphere) over a wide range of scales (small scale phenomena in unstably stratified and convectively mixed layers to deep convection in the atmosphere and ocean), by different research methods (field measurements, laboratory simulations, numerical modelling), and within a variety of application areas (dispersion of pollutants, weather forecasting, hazardous phenomena associated with buoyant forcing).

Download or read book Observation Characteristics and Formation Mechanisms of Severe Weather Events written by Jianhua Sun and published by Frontiers Media SA. This book was released on 2023-11-16 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book World Weather Program written by and published by . This book was released on 1977 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Air Pollution Modeling and Its Application VIII written by H. Van Dop and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 759 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1949, when the North Atlantic Treaty was ratified, one of its articles explicitly noted '1hat member countries should contribute towards the further development of peaceful and friendly international relations." Specific problems related to the human environment were addressed by the Committee of Challenges of Modern Society (CCMS) of NATO, established in 1969. This provided a framework within which a series of International Technical Meetings (ITMs) on Air Pollution Modelling has been held. This volume documents the proceedings of the 18th meeting in this series. Science, like the arts and sports, provides an ideal vehicle for "developing peaceful and friendly international relations". National boundaries have never been barriers to the movement of air pollution, and fortunately this has also proved true of scientists studying the transport of air pollution. It is thus satisfying to record that since the mid-seventies it has been commonplace to find Eastern European scientists among attendees at the ITMs which have (in a very modest way) participated in a precursor to the process which has led to historical changes in Europe and which will undoubtedly lead to a tremendous increase in personal and intellectual exchange on a worldwide basis.

Download or read book Atmospheric Turbulence and Air Pollution Modelling written by F.T. Nieuwstadt and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 375 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of turbulence in the atmosphere has seen considerable progress in the last decade. To put it briefly: boundary-layer meteorology, the branch of atmospheric science that concentrates on turbulence in the lower atmosphere, has moved from the surface layer into the boundary layer itself. The progress has been made on all fronts: theoretical, numerical and observational. On the other hand, air pollution modeling has not seen such a rapid evolution. It has not benefited as much as it should have from the increasing knowledge in the field of atmospheric turbulence. Air pollution modeling is still in many ways based on observations and theories of the surface layer only. This book aims to bring the reader up to date on recent advances in boundary-layer meteorology and to pave the path for applications in air pollution dispersion problems. The text originates from the material presented during a short course on Atmospheric Turbulence and Air Pollution Modeling held in The Hague during September 1981. This course was sponsored and organized by the Royal Netherlands Meteorological Institute, xi xii PREFACE to which both editors are affiliated. The Netherlands Government Ministry of Health and Environmental Protection and the Council of Europe also gave support.

Download or read book Monthly Weather Review written by and published by . This book was released on 2004 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Global Energy and Water Cycles written by K. A. Browning and published by Cambridge University Press. This book was released on 1999-02 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive treatment of models and processes related to water fluxes for meteorologists, hydrologists and oceanographers.