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 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 Oceanography written by and published by . This book was released on 2002 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 1 32 Degree Real Time Global Ocean Prediction and Value Added Over 1 16 Degree Resolution written by and published by . This book was released on 2007 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A 1/32 degree global ocean nowcast/forecast system has been developed by the Naval Research Laboratory at the Stennis Space Center. It started running at the Naval Oceanographic Office in near real-time on 1 Nov. 2003 and has been running daily in real-time since I Mar. 2005. It became an operational system on 6 March 2006, replacing the existing 1/16 degree system which ceased operation on 12 March 2006. Both systems use the NRL Layered Ocean Model (NLOM) with assimilation of sea surface height from satellite altimeters and sea surface temperature from multi-channel satellite infrared radiometers. Real-time and archived results are available online at http://www.ocean.nrlssc.navy.mil/global%5Fnlom. The 1/32 degree system has improvements over the earlier system that can be grouped into two categories: (1) better resolution and representation of dynamical processes and (2) design modifications. The design modifications are the result of accrued knowledge since the development of the earlier 1/16 degree system. The improved horizontal resolution of the 1/32 degree system has significant dynamical benefits which increase the ability of the model to accurately nowcast and skillfully forecast.
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 Validation Test Report for the Coupled Ocean Atmosphere Mesoscale Prediction System COAMPS Version 5 0 written by and published by . This book was released on 2010 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) is coupled utilizing the Earth System Modeling Framework and validated for five test cases: 1) Adriatic Sea, 2) Ligurian Sea, 3) Monterey Bay, CA, 4) Kuroshio Extension System Study and 5) Coastal Peru. The COAMPS system makes use of meteorological observations including radiosondes, satellite data, ship reports, and ocean observations with time-dependent global atmospheric lateral boundary conditions from the Navy Operational Global Atmospheric Prediction System (NOGAPS). Time-dependent ocean boundary conditions are derived from global the Navy Coastal Ocean Model. Atmospheric and oceanographic forecast model output includes surface and upper-air meteorological fields, sea surface temperature (SST), three-dimensional (3D) ocean temperature (T), and salinity (S), velocity, two-dimensional (2D) mixed layer depth (MLD) and ocean acoustic products. The validation efforts contained in this report focus on the upper ocean (mixed layer), heat fluxes, near surface winds, temperature, moisture, the air-sea interaction, and marine boundary layer characteristics.
Download or read book PCTides Validation Test Report written by and published by . This book was released on 2006 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Naval Research Laboratory (NRL) has built a globally relocatable tide-surge forecast system. Currently, this system runs on a UNIX platform, but was originally designed for PC-based use, and, as such, is referred to as "PCTides." The system is composed of a two-dimensional barotropic ocean model, which is driven by tidal forcing and/or surface wind and pressure forcing. PCTides is applied to the user's area of interest to provide a hindcast or forecast of tidal amplitude, phase and two-dimensional barotropic ocean currents. The PCTides system uses the solutions from a global tide model Finite Element Solutions 99 (FES99) to provide global boundary conditions. The system also contains a 2-min global bathymetry database (the NRL DBDB2 database) to define the model's geometry and bathymetry. Wind forcing for PCTides comes from a number of sources. If the user has access, the Navy's Global Atmospheric Prediction System (NOGAPS), or the Coupled Ocean & Atmospheric Mesocale Prediction system (COAMPS) may be used. Based on this model, hurricane forcing can be generated that can provide surface pressure and winds to drive the two-dimensional barotropic ocean model and generate a storm surge. One major advantage of PCTides is that the model has the ability to be rapidly relocated to areas of interest. The tidal heights can be generated at a user-specified latitude/longitude position and, therefore, is not dependent on a tidal "look up" table or preexisting database of preselected locations.
Download or read book 1 32 DEGREE Global Ocean Modeling and Prediction written by and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This DoD HPC Challenge project is a crucial component of an effort to develop a data-assimilative 1/320 global ocean nowcast/forecast system, which includes the associated basic research and exploratory development. The need for 1/320 resolution ( -3.5 km at mid-latitudes) has been demonstrated through extensive research, including essential contributions from our FY97 and FY98/00 DoD HPC Challenge projects. The ocean model, after 30 years of climatological spinup, was run interannually spanning the period 1979-present Data assimilation experiments are currently underway. Transition of this system to operational use at the Naval Oceanographic Office (NA VO) is planned for later in 2003.
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 Ocean Forecasting written by Nadia Pinardi and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Advanced Study Courses in the field of Marine Science and Technology were part of the training programme developed from 1989 until 1999 within MAST, the Marine Science and Technology Programme of the European Union. They were related to the core topics of MAST Programme, marine systems research, extreme marine environments, regional Sea research, coastal systems research and engineering, and marine technology. The main objectives of these study courses were to further advance education in topics at the forefront of scien tific and technological development in Europe, and to improve the communication between students and experienced scientists on a European and international level. Over the years the Programme sponsored around 30 Advanced Study Courses. They took place in ten different member states of the European Union and their contribution in the formation of a European scientific community was significant. They also encouraged exchanges and contacts with several countries around the world such as United States, the third Mediterranean countries and others. The Course on Ocean Forecasting was one ofthe most successful with regard to its con tent, number of applications for participation and students satisfaction. When considering the need for the Advanced Study Course on Ocean Forecast ing, it is important to remember that the Oceans and Seas have always played a central role throughout the history of mankind. This is seen from the times of the ancient civilizations ofEgypt and Greece with the Phoenician traders, to the Viking voyages of exploration and discovery in medieval times.
Download or read book Atmospheric Rivers written by F. Martin Ralph and published by Springer Nature. This book was released on 2020-07-10 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the standard reference based on roughly 20 years of research on atmospheric rivers, emphasizing progress made on key research and applications questions and remaining knowledge gaps. The book presents the history of atmospheric-rivers research, the current state of scientific knowledge, tools, and policy-relevant (science-informed) problems that lend themselves to real-world application of the research—and how the topic fits into larger national and global contexts. This book is written by a global team of authors who have conducted and published the majority of critical research on atmospheric rivers over the past years. The book is intended to benefit practitioners in the fields of meteorology, hydrology and related disciplines, including students as well as senior researchers.
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.
Download or read book Data Assimilation for Atmospheric Oceanic and Hydrologic Applications Vol II written by Seon Ki Park and published by Springer Science & Business Media. This book was released on 2013-05-22 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the most recent progress in data assimilation in meteorology, oceanography and hydrology including land surface. It spans both theoretical and applicative aspects with various methodologies such as variational, Kalman filter, ensemble, Monte Carlo and artificial intelligence methods. Besides data assimilation, other important topics are also covered including targeting observation, sensitivity analysis, and parameter estimation. The book will be useful to individual researchers as well as graduate students for a reference in the field of data assimilation.
Download or read book Satellite Altimetry Over Oceans and Land Surfaces written by Detlef Stammer and published by CRC Press. This book was released on 2017-10-31 with total page 617 pages. Available in PDF, EPUB and Kindle. Book excerpt: Satellite remote sensing, in particular by radar altimetry, is a crucial technique for observations of the ocean surface and of many aspects of land surfaces, and of paramount importance for climate and environmental studies. This book provides a state-of-the-art overview of the satellite altimetry techniques and related missions, and reviews the most-up-to date applications to ocean dynamics and sea level. It also discusses related space-based observations of the ocean surface and of the marine geoid, as well as applications of satellite altimetry to the cryosphere and land surface waters; operational oceanography and its applications to navigation, fishing and defense.
