Download or read book Performance of a High Resolution Diagnostic Model for Short Range Mesoscale Wind Forecasts in Complex Terrain written by Shawn G. Gallaher and published by . This book was released on 2002-09-01 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study investigates the feasibility of using a high resolution simple diagnostic model (WOCSS) initialized from a coarser grid full physics prognostic model (COAMPS) to obtain mesoscale winds. This approach using COAMPS 81, 27, and 9 km forecast model soundings to initialize WOCSS at 3 km is compared to COAMPS forecast at 3km horizontal resolution alone. Four case studies were collected during various weather regimes in Central California. Observations were collected from 5 different agencies and were used for verification of the models. The sensitivity of various WOCSS parameters were also explored. The results showed that overall the COAMPS(9km)/WOCSS approach provides winds as good as COAMPS at 3 km at a greatly reduced computation time. The COAMPS/WOCSS methodology performed particularly well during non-frontal situations where low-level inversions were present. Separation of the surface observation data by agency revealed large errors from data networks with low maintenance, monitoring and site specifications standards. The highest flow surface in WOCSS was the only parameter that displayed any significant sensitivity. Further work is needed to test the advantages of this sensitivity. COAMPS/WOCSS mesoscale forecast winds may prove to be very useful as input to emergency response applications such as dispersion and trajectory modeling.
Download or read book Evaluation of High Density Surface Observations in Complex Terrain and Their Contribution to the MM5 Model written by and published by . This book was released on 2007 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study evaluates the data assimilation capabilities of Three Dimensional Multiquadric Interpolation (3DMQ) and the MM5 model when incorporating mesoscale observations from the United States Air Force Academy (USAFA) High Wind Alert system (HWAS). These mesoscale observations are incorporated into a triple nested (12, 4, and 1.33 km) high resolution model simulation and evaluated for their impact upon analyzed and forecasted wind values at USAFA during a severe downslope wind event that occurred on 6 March 2004. This evaluation is the first step in developing future forecasting and analysis tools for use by the military in various operations in complex terrain. The development of deployable automated tactical weather sensors in forward deployed locations requires an evaluation of the impact and usefulness these sensors would have on analysis forecast tools and mesoscale Numerical Weather Prediction (NWP) models. The juxtaposition of the HWAS network in complex terrain and the aviation training operations at USAFA provides an ideal set of data, mission and location for testing and evaluating a high resolution nested grid mesoscale NWP model. This study shows that incorporating HWAS observations into the 3DMQ data assimilation process has a significant impact upon verification of analyzed wind fields with the biggest impact occurring at the 1.33 km grid scale. Using these analyzed fields as initial conditions for MM5 model simulations, this study shows the ability of the 1.33 km model forecast wind fields to verify significantly better than either the 4 or 12 km through 18, 24, and 30 hour forecasts. Additionally, this study shows the limited, yet discernable impact HWAS observations have upon forecasted winds in the first several hours of MM5 model runs during a severe downslope wind event at USAFA.
Download or read book Prototype of a Coupled Mesoscale microscale Modeling System written by Saba A. Luces and published by . This book was released on 2006 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: A prototype system of coupled mesoscale and microscale models was developed to produce and analysis that considered higher-resolution terrain. Research was initiated to integrate the microscale code with the mesoscale code to attain higher-resolution meteorological forecasts for target areas and other localized areas on the battlefield. A step-wise approach was employed to develop a modular prototype that would first show improved winds using high-resolution diagnostic models, but then be capable of interchanging various components. The San Francisco Bay area was selected as the common simulation domain, since both models had already been run there in previous studies.
Download or read book Nowcasting II written by B. Battrick and published by . This book was released on 1984 with total page 548 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 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Weather Research and Forecasting Model Wind Sensitivity Study at Edwards Air Force Base CA written by Leela Ramaswamy Watson and published by . This book was released on 2008 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Mesoscale Predictability of Terrain Induced Flows written by and published by . This book was released on 2010 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The long-term goal of this research is to develop an understanding of the predictability of small-scale atmospheric circulations appearing in forecasts generated by state-of-the-art, high-resolution mesoscale models. Using previously collected observations and archived simulations performed using the Navy's Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) model, as well as new simulations, we focus on assessing the predictability of winds, mountain waves, and clear air turbulence (CAT) in the lee of the Sierra Nevada. The specific questions addressed in our research are as follows: (1) How sensitive are downslope winds to atmospheric conditions upstream of the mountain barrier?; (2) When such sensitivity is not extreme, can forecast errors in downslope winds and mountain-wave structure be linked to large characteristic errors in the atmospheric conditions forecast to occur on the upstream side of the mountains?; (3) Can systematic improvements in COAMPS be identified to remove these errors?; and (4) What do ensemble forecasts indicate about the sensitivity of downslope winds and mountain waves to the upstream conditions, and how can such forecasts be best used to predict these events? The answers to these questions are of direct benefit to operational forecasters using COAMPS to produce aviation and other forecasts over complex terrain. Although the focus is on the forecasting of terrain-induced mesoscale disturbances, these findings are likely to be relevant to the predictability of other mesoscale phenomena. The investigators used the COAMPS model to conduct a series of 70-member ensemble simulations of high-wind events observed during the Terrain-Induced Rotors Experiment (T-REX). By examining the ensemble spread, they obtained an unprecedentedly complete description of the sensitivity of mountain waves, CAT, and downslope winds to small variations in the initial conditions.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1994 with total page 806 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book Air Pollution Modeling and Its Application X written by Sven-Erik Gryning and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 20th International Technical Meeting on Air Pollution Modelling and Its Application was held in Valencia, Spain, during late 1993. At this conference, a new record of abstracts was submitted, a new record of scientists participated, and a new record of countries was represented. This clearly indicates society's continuous and growing interest in, as well as importance of, the complexities associated with the modelling of air pollution. The conference addressed the following main subjects: integrated regional modelling, global and long-range transport, new modelling developments, accidental releases, and model assess ment and verification. In addition, two project-oriented workshops were organized as part of the conference. The many contributing authors and scientists taking active part in the discussions following the papers, have made this proceeding a record of the current status in the field of air pollu tion modelling. We want to express our gratitude to their efforts. We also wish to extend our gratitude to the sponsors that made this conference possible. In addition to financial support from NATOjCCMS the conference received contributions from CEAM, the European Asso ciation for the Science of Air Pollution, Danish Center for Air Research, and Ris0 National Laboratory. A special grant was given by NATOjCCMS to facilitate attendance of scientists from Central and Eastern Europe. We also wish to express our gratitude to Rosa Salvador and Pilar Zamora of CEAM, who laboriously organized the conference pre-proceedings, and to Anne N0rregaard and Ulla Riis Christiansen of Ris0 National Laboratory, who seved as conference secretariat.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atmospheric and Dispersion Modeling in Areas of Highly Complex Terrain Employing a Four dimensional Data Assimilation Technique written by and published by . This book was released on 1994 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of this study indicate that the current data assimilation technique can have a positive impact on the mesoscale flow fields; however, care must be taken in its application to grids of relatively fine horizontal resolution. Continuous FDDA is a useful tool in producing high-resolution mesoscale analysis fields that can be used to (1) create a better initial conditions for mesoscale atmospheric models and (2) drive transport models for dispersion studies. While RAMS is capable of predicting the qualitative flow during this evening, additional experiments need to be performed to improve the prognostic forecasts made by RAMS and refine the FDDA procedure so that the overall errors are reduced even further. Despite the fact that a great deal of computational time is necessary in executing RAMS and LPDM in the configuration employed in this study, recent advances in workstations is making applications such as this more practical. As the speed of these machines increase in the next few years, it will become feasible to employ prognostic, three-dimensional mesoscale/transport models to routinely predict atmospheric dispersion of pollutants, even to highly complex terrain. For example, the version of RAMS in this study could be run in a ''nowcasting'' model that would continually assimilate local and regional observations as soon as they become available. The atmospheric physics in the model would be used to determine the wind field where no observations are available. The three-dimensional flow fields could be used as dynamic initial conditions for a model forecast. The output from this type of modeling system will have to be compared to existing diagnostic, mass-consistent models to determine whether the wind field and dispersion forecasts are significantly improved.
Download or read book The Representation of Cumulus Convection in Numerical Models written by Kerry Emanuel and published by Springer. This book was released on 2015-03-30 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents descriptions of numerical models for testing cumulus in cloud fields. It is divided into six parts. Part I provides an overview of the problem, including descriptions of cumulus clouds and the effects of ensembles of cumulus clouds on mass, momentum, and vorticity distributions. A review of closure assumptions is also provided. A review of "classical" convection schemes in widespread use is provided in Part II. The special problems associated with the representation of convection in mesoscale models are discussed in Part III, along with descriptions of some of the commonly used mesoscale schemes. Part IV covers some of the problems associated with the representation of convection in climate models, while the parameterization of slantwise convection is the subject of Part V.
Download or read book National Implementation Plan for the Modernization and Associated Restructuring of the National Weather Service written by United States. National Weather Service and published by . This book was released on 1992 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hind casting of High Resolution Atmospheric Fields Over Complex Terrain Model Initialization Issues written by and published by . This book was released on 2003 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: British Columbia has expressed interest in the development of a five-year database of atmospheric conditions at high spatial & temporal resolution to support regulatory dispersion modelling activities & characterization of airsheds outside the Lower Fraser Valley. The focus of this study is to determine if there is a significant improvement in mesoscale model performance when the model is run in hindcast mode using analysis fields every six hours, rather than real-time mode using forecast fields every three hours. As a test, a series of high-resolution (one kilometre) simulations over the Thomson-Okanagan area was conducted with the Regional Atmospheric Modelling System. Simulated fields from both modelling strategies are compared to real observations of surface wind direction & velocity.
Download or read book Mountain Meteorology written by C. David Whiteman and published by Oxford University Press. This book was released on 2000-06-01 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mountain Meteorology: Fundamentals and Applications offers first an introduction to the basic principles and concepts of mountain meteorology, then goes on to discuss their application in natural resources management. It includes over two hundred beautiful, full-color photographs, figures, and diagrams, as well as observable indicators of atmospheric processes--such as winds, temperature, and clouds--to facilitate the recognition of weather systems and events for a variety of readers. It is ideal for those who spend time in or near mountains and whose daily activities are affected by weather. As a comprehensive work filled with diverse examples and colorful illustrations, it is essential for professionals, scholars, and students of meteorology.
Download or read book An Evaluation of High resolution Modeling and Statistical Forecast Techniques Over Complex Terrain written by Kenneth Alan Hart and published by . This book was released on 2004 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
