Download or read book Validation Test Report for OCEANS 1 0 The 1 40 Global Reduced Gravity NRL Layered Ocean Model written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The components of OCEANS 1.0 are described in this report. They consist of the marginally eddy-resolving 1/4 deg global, reduced gravity NRL (Naval Research Laboratory) Layered Ocean Model (NLOM) and the Pacific West Coast (PWC) model. The reduced gravity version of NLOM is capable of accurately depicting the large-scale oceanic circulation, but there are a few exceptions. The version of NLOM described here is wind-forced only, with no assimilation of altimeter or infrared frontal data. Thus, it cannot be expected to produce accurate hindcasts of sea surface height or upper layer velocities in regions dominated by mesoscale flow instabilities. Maps are provided to show the relative importance of direct wind forcing (deterministic) versus flow instabilities (nondeterministic). NLOM has mixed success in hindcasting sea level variations when compared to observed tide gauges; however, some of its highest correlations are at stations within the PWC domain. A comparison between observed and NLOM simulated drifting buoys has also been made. Ensemble forecasts of four model simulations generally produce an average simulated track that is closer to the observed drifter than any single simulation. However, the model cannot consistently beat a persistence forecast due to the large amount of nondeterminism in the upper layer velocity fields. NLOM will also provide boundary conditions for the PWC model. Two PWC simulations were run, one using climatologically wind-forced NLOM boundary conditions and one using climatologically wind-forced NLOM boundary conditions. The latter case showed improved sea level correlation over the former case. Satellite altimetry assimilation and a refinement in the boundary condition implementation should further improve the results. Due to the limitations in physics of the 1/4 deg reduced gravity NLOM and the lack of satellite data assimilation, it is recommended that OCEANS 1.0 not enter operational check/test mode.
Download or read book Validation Test Report for the 1 16 Degree Global NRL Layered Ocean Model Nowcast Forecast System written by Robert C. Rhodes and published by . This book was released on 2003-04-01 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes validation tests for the eddy-resolving 1/16 degree global Naval Research Laboratory (NRL) Layered Ocean Model (NLOM) nowcast/forecast system. For the nonassimilative model, maps of sea surface height (SSH) and sea surface temperature (SST) show that the model depicts the observed positions of the major fronts. Comparisons of model SSH variability with altimetry and correlations with tide-gauge SSH time series demonstrate ocean model skill. In addition, model comparisons with daily buoy time series of SST indicate that the model has SST simulation skill when forced by winds and thermal forcing. The realistic nonassimilative model simulation skill indicates that the model will add skill to the data assimilation cycle and, in the case of SSH assimilation, allow the model to be used as the first-guess for the analysis. Validation tests of the assimilative model were performed. SST comparisons with unassimilated buoy time series show that the model has good agreement with the observed data. SSH comparisons with observed sea level from coastal stations and buoys indicate that the model has accurate SSH and the correlations are higher with data assimilation. Nowcast comparisons with analyzed frontal positions from the Naval Oceanographic Office show that the model can be a useful tool to help the analyst improve frontal analyses. Forecast evaluations indicate that the model has SSH predictive skill of at least 30 days in the Kuroshio Extension, about 15 days in the Gulf Stream, and at least 30 days when calculated globally. The NLOM system was also tested for improvement of the Modular Ocean Data Assimilation System (MODAS) synthetic temperature profiles by using the NLOM SSH field as opposed to the MODAS 2-D SSH analysis field. Results indicate that the synthetics from NLOM SSH are, in general, better than MODAS SSH. (2 tables, 50 figures, 34 refs.)
Download or read book Validation Test Report for the 1 16 Degree Global NRL Layered Ocean Model Nowcast Forecast System written by and published by . This book was released on 2003 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes validation tests for the eddy-resolving 1/16 degree global Naval Research Laboratory (NRL) Layered Ocean Model (NLOM) nowcast/forecast system. For the nonassimilative model, maps of sea surface height (SSH) and sea surface temperature (SST) show that the model depicts the observed positions of the major fronts. Comparisons of model SSH variability with altimetry and correlations with tide-gauge SSH time series demonstrate ocean model skill. In addition, model comparisons with daily buoy time series of SST indicate that the model has SST simulation skill when forced by winds and thermal forcing. The realistic nonassimilative model simulation skill indicates that the model will add skill to the data assimilation cycle and, in the case of SSH assimilation, allow the model to be used as the first-guess for the analysis. Validation tests of the assimilative model were performed. SST comparisons with unassimilated buoy time series show that the model has good agreement with the observed data. SSH comparisons with observed sea level from coastal stations and buoys indicate that the model has accurate SSH and the correlations are higher with data assimilation. Nowcast comparisons with analyzed frontal positions from the Naval Oceanographic Office show that the model can be a useful tool to help the analyst improve frontal analyses. Forecast evaluations indicate that the model has SSH predictive skill of at least 30 days in the Kuroshio Extension, about 15 days in the Gulf Stream, and at least 30 days when calculated globally. The NLOM system was also tested for improvement of the Modular Ocean Data Assimilation System (MODAS) synthetic temperature profiles by using the NLOM SSH field as opposed to the MODAS 2-D SSH analysis field. Results indicate that the synthetics from NLOM SSH are, in general, better than MODAS SSH. (2 tables, 50 figures, 34 refs.).
Download or read book Validation Test Report for the 1 8 Deg Global Navy Coastal Ocean Model Nowcast Forecast System written by and published by . This book was released on 2007 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: The global Naval Coastal Ocean Model (NCOM) is a 1/8 degree global application of NCOM developed by the Naval Research Laboratory (NRL) for use at the Naval Oceanographic Office (NAVOCEANO) as part of an assimilative ocean model nowcast/forecast system. Global NCOM is the first operational global ocean model that has sufficient resolution to be eddy-permitting. Global NCOM supports predictions of ocean currents, temperatures, salinity, sea surface height, and sound speed both directly and by providing initial and boundary conditions for higher-resolution nested ocean models. The forecast system addresses Navy requirements for Numerical Modeling (METOC 9801), High Resolution Surface and Subsurface Currents (METOC 9308), Littoral Salinity Prediction (METOC 9902), and Air-Sea Drift Prediction (METOC 9115). This validation test report describes global NCOM, its use in an assimilative forecast system, and evaluation of assimilative and non-assimilative products using independent climatologies and observations.
Download or read book O ti ss hsiang y ch an li ch ng chih lun chi written by and published by . This book was released on 1959 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Validation Test Report for the Global Ocean Forecast System V3 0 1 12 Deg HYCOM NCODA Phase II written by and published by . This book was released on 2010 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Global Ocean Forecast System Version 3.0 (V3.0) is comprised of the 1/12 deg global HYbrid Coordinate Ocean Model (HYCOM) and the Navy Coupled Ocean Data Assimilation (NCODA) system. It is a next-generation system capable of nowcasting and forecasting the oceanic "weather," which includes the three-dimensional ocean temperature, salinity and current structure, the surface mixed layer and the location of mesoscale features such as eddies, meandering currents and fronts. V3.0 is scheduled to replace the existing nowcast/forecast system (V2.6) based on the 1/8 deg Navy Coastal Ocean Model (NCOM), 1/32 deg Navy Layered Ocean Model (NLOM), 1/8 deg Modular Ocean Data Analysis System (MODAS) and NCODA. This Phase II report describes the validation testing performed on one-year hindcasts of V3.0 and V2.6. A few Phase I tasks (temperature vs. depth and acoustical proxy error analyses) have been re-evaluated along with new evaluations examining a) each system as a provider of boundary conditions to a regional nested model, b) 14-day forecast skill relative to climatology and persistence of temperature vs. depth, c) 14-day forecast skill of acoustical proxies, d) 14-day forecast skill of sea surface height and sea surface temperature, and e) a velocity comparison against glider and drifting buoy observations. Overall, this report has determined that GOFS V3.0 is performing equal to or notably better than GOFS V2.6. The superior performance of V3.0 is especially evident in providing boundary contitions to regional nested models, an important function of a global ocean nowcast/forecast system.
Download or read book Formulation of the NRL Layered Ocean Model in Spherical Coordinates written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes NRL's hydrodynamic (isopycnal) nonlinear, primitive equation, ocean circulation model in a spherical layer suitable for a large basin or the global domain. This document should be read in conjunction with NOARL Report 35, December 1991, The Navy Layered Ocean Model User's Guide?25Z. Spherical geometry requires careful treatment of the equations of fluid dynamics to ensure spurious terms are not introduced during the layer averaging process, particularly in the momentum diffusion expressions. From these layer averaged equations, finite difference approximations are derived on a grid of uniform intervals in longitude and latitude (not necessarily the same). These equations may be solved efficiently on modern architecture scientific computers, allowing accurate description of ocean flows.
Download or read book The Navy Layered Ocean Model Users Guide written by Alan J. Wallcraft and published by . This book was released on 1991 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Next Generation Earth System Prediction written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2016-08-22 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the nation's economic activities, security concerns, and stewardship of natural resources become increasingly complex and globally interrelated, they become ever more sensitive to adverse impacts from weather, climate, and other natural phenomena. For several decades, forecasts with lead times of a few days for weather and other environmental phenomena have yielded valuable information to improve decision-making across all sectors of society. Developing the capability to forecast environmental conditions and disruptive events several weeks and months in advance could dramatically increase the value and benefit of environmental predictions, saving lives, protecting property, increasing economic vitality, protecting the environment, and informing policy choices. Over the past decade, the ability to forecast weather and climate conditions on subseasonal to seasonal (S2S) timescales, i.e., two to fifty-two weeks in advance, has improved substantially. Although significant progress has been made, much work remains to make S2S predictions skillful enough, as well as optimally tailored and communicated, to enable widespread use. Next Generation Earth System Predictions presents a ten-year U.S. research agenda that increases the nation's S2S research and modeling capability, advances S2S forecasting, and aids in decision making at medium and extended lead times.
Download or read book Ocean Modeling in an Eddying Regime written by Matthew W. Hecht and published by John Wiley & Sons. This book was released on 2013-04-30 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 177. This monograph is the first to survey progress in realistic simulation in a strongly eddying regime made possible by recent increases in computational capability. Its contributors comprise the leading researchers in this important and constantly evolving field. Divided into three parts Oceanographic Processes and Regimes: Fundamental Questions Ocean Dynamics and State: From Regional to Global Scale, and Modeling at the Mesoscale: State of the Art and Future Directions The volume details important advances in physical oceanography based on eddy resolving ocean modeling. It captures the state of the art and discusses issues that ocean modelers must consider in order to effectively contribute to advancing current knowledge, from subtleties of the underlying fluid dynamical equations to meaningful comparison with oceanographic observations and leading-edge model development. It summarizes many of the important results which have emerged from ocean modeling in an eddying regime, for those interested broadly in the physical science. More technical topics are intended to address the concerns of those actively working in the field.
Download or read book Middle Atmosphere written by PLUMB and published by Birkhäuser. This book was released on 2013-11-21 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: PAGEOPH, stratosphere, these differences provide us with new evidence, interpretation of which can materially help to advance our understanding of stratospheric dynamics in general. It is now weil established that smaller-scale motions-in particular gravity waves and turbulence-are of fundamental importance in the general circulation of the mesosphere; they seem to be similarly, if less spectacularly, significant in the troposphere, and probably also in the stratosphere. Our understanding of these motions, their effects on the mean circulation and their mutual interactions is progressing rapidly, as is weil illustrated by the papers in this issue; there are reports of observational studies, especially with new instruments such as the Japanese MV radar, reviews of the state of theory, a laboratory study and an analysis of gravity waves and their effects in the high resolution "SKYHI" general circulation model. There are good reasons to suspect that gravity waves may be of crucial significance in making the stratospheric circulation the way it is (modeling experience being one suggestive piece of evidence for this). Direct observational proof has thus far been prevented by the difficulty of making observations of such scales of motion in this region; in one study reported here, falling sphere observations are used to obtain information on the structure and intensity of waves in the upper stratosphere.
Download or read book Climatological Atlas of the World Ocean written by Sydney Levitus and published by . This book was released on 1982 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ocean Circulation written by Rui Xin Huang and published by Cambridge University Press. This book was released on 2010 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: It provides a concise introduction to the dynamics and thermodynamics of oceanic general circulation.
Download or read book Space Shuttle Missions Summary NASA TM 2011 216142 written by Robert D. Legler and published by www.Militarybookshop.CompanyUK. This book was released on 2011-09-01 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Full color publication. This document has been produced and updated over a 21-year period. It is intended to be a handy reference document, basically one page per flight, and care has been exercised to make it as error-free as possible. This document is basically "as flown" data and has been compiled from many sources including flight logs, flight rules, flight anomaly logs, mod flight descent summary, post flight analysis of mps propellants, FDRD, FRD, SODB, and the MER shuttle flight data and inflight anomaly list. Orbit distance traveled is taken from the PAO mission statistics.
Download or read book Geoid Determination written by Fernando Sansò and published by Springer Science & Business Media. This book was released on 2013-02-13 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will be based on the material of the lecture noties in several International Schools for the Determination and Use of the Geoid, organized by the International Geoid Serivice of the International Association of Geodesy. It consolidates, unifies, and streamlines this material in a unique way not covereed by the few other books that exist on this subjext. More specifically, the book presents (for the first time in a single volume) the theory and methodology of the most common technique used for precise determination of the geoid, including the computation of the marine geoid from satellite altimetry data. These are illustrated by specific examples and actual computations of local geoids. In addition, the book provides the fundamentals of estimating orthometric heights without spirit levelling, by properly combining a geoid with heights from GPS. Besides the geodectic and geophysical uses, this last application has made geoid computation methods very popular in recent years because the entire GPS and GIS user communities are interested in estimating geoid undulations in order to convert GPS heights to physically meaningful orthometric heights (elevations above mean sea level). The overall purpose of the book is, therefore, to provide the user community (academics, graduate students, geophysicists, engineers, oceanographers, GIS and GPS users, researchers) with a self-contained textbook, which will supply them with the complete roadmap of estimating geoid undulations, from the theoretical definitions and formulas to the available numerical methods and their implementation and the test in practice.
Download or read book New Frontiers in Operational Oceanography written by Godae GODAE OceanView and published by Createspace Independent Publishing Platform. This book was released on 2018-09-03 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: The implementation of operational oceanography in the past 15 years has provided many societal benefits and has led to many countries adopting a formal roadmap for providing ocean forecasts. Continuing the tradition of two very successful international summer schools held in France in 2004 (Chassignet and Verron, 2006) and in Australia in 2010 (Schiller and Brassington, 2011), a third international school that focused on frontier research in operational oceanography was held in Majorca in 2017. In the coming years, graduate students and young scientists will be challenged by many new observations (SWOT, Sentinel, AUVs, floats, etc.), complex high resolution numerical models and data assimilation (high resolution, predictability, uncertainty, changing computing platforms, etc.), and the need to work on many scales (open ocean-shelf interactions, coupled ocean-ice-atmosphere, biogeochemistry, etc.). The latter school brought together senior experts and young researchers (pre- and post-doctorate) from across the world and exposed them to the latest research in oceanography, specifically how it will impact operational oceanography. This book is a compilation of the lectures presented at the school and presents a summary of the current state-of-the-art in operational oceanography research. About the Editors: Eric P. Chassignet is a professor of Physical Oceanography in the Department of Earth, Ocean and Atmospheric Science and director of the Center for Ocean-Atmospheric Prediction Studies at Florida State University (Tallahassee, FL, USA). Ananda Pascual is a research scientist at the Instituto Mediterráneo de Estudios Avanzados, IMEDEA(CSIC-UIB) in Esporles (Majorca, Spain). Joaquin Tintore is professor of Physical Oceanography at IMEDEA and director of SOCIB (Sistema d'Observacio iPredictio Coastaner de les Iles Balears) in Palma (Majorca, Spain). Jacques Verron is a senior research scientist emeritus at the Institut des Geosciences de l'Environnement (IGE) (Grenoble, France). About GODAE OceanView: GODAE OceanView provides coordination and leadership in consolidating and improving global and regional ocean analysis and forecasting systems on an international level. It encourages international collaboration to address the scientific and technical challenges associated with operational oceanography. It also fosters research that will lead to the enhancement of existing systems and the development of next generation of ocean prediction systems.
Download or read book Understanding and Predicting the Gulf of Mexico Loop Current written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2018-05-23 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most significant, energetic, yet not well understood, oceanographic features in the Americas is the Gulf of Mexico Loop Current System (LCS), consisting of the Loop Current (LC) and the Loop Current Eddies (LCEs) it sheds. Understanding the dynamics of the LCS is fundamental to understanding the Gulf of Mexico's full oceanographic system, and vice versa. Hurricane intensity, offshore safety, harmful algal blooms, oil spill response, the entire Gulf food chain, shallow water nutrient supply, the fishing industry, tourism, and the Gulf Coast economy are all affected by the position, strength, and structure of the LC and associated eddies. This report recommends a strategy for addressing the key gaps in general understanding of LCS processes, in order to instigate a significant improvement in predicting LC/LCE position, evolving structure, extent, and speed, which will increase overall understanding of Gulf of Mexico circulation and to promote safe oil and gas operations and disaster response in the Gulf of Mexico. This strategy includes advice on how to design a long-term observational campaign and complementary data assimilation and numerical modeling efforts.
