| Bubble Clustering in the Ocean and Acoustic Implications |
Nov-2009 |
5 pages |
| Authors:
Thomas C Weber; NEW HAMPSHIRE UNIV DURHAM CENTER FOR COASTAL AND OCEAN MAPPING (CCOM)
|
 | This research is intended to further the understanding of how high-frequency acoustic fields interact with bubble clouds in highly dynamic environments (e.g., in ship wakes or near the ocean surface). The results of this type of research can be used to help refine high frequency sonar performance models, to select optimal sonar frequencies, and to refine detection and classification routines. The results of this research can also be used to ... |
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| Comparisons of Monthly Mean 10 M Wind Speeds from Satellites and NWP Products Over the Global Ocean |
09-Oct-2009 |
15 pages |
| Authors:
Charlie Barron; E J Metzger; Alan J Wallcraft; Ahmet B Kara; R Pauley; M Bourassa; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| The accuracy of wind speed at 10 m above the sea surface from two satellite and three numerical weather prediction (NWP) products is investigated over the global ocean. Rain-free equivalent neutral winds from the Quick Scatterometer (QuikSCAT) are converted to stability-dependent winds to be consistent with those from NWP products and are taken as truth in comparisons to winds from other products. Quantitative statistical analyses presented at each grid point ... |
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| Planning the Optimal Transit for a Ship Through a Mapped Minefield |
Sep-2009 |
66 pages |
| Authors:
Pei-Chieh Li; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF OPERATIONS RESEARCH
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| This thesis develops (a) a mission-planning tool for a Navy Mine Counter Measure (MCM) force to find a minimum-risk route for a surface ship through a mapped minefield, and (b) a heuristic to identify a sequence of mines whose clearance (removal and/or deactivation) leads to a rapid reduction of the risk of a minimum-risk path. All modeling concepts reflect the requirements of the Republic of China Navy's MCM operations. The ... |
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| Long-Range Atmosphere-Ocean Forecasting in Support of Undersea Warfare Operations in the Western North Pacific |
Sep-2009 |
98 pages |
| Authors:
Sarah L Heidt; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| Skillful long-range forecasts of acoustic variables have the potential to be very useful in planning Navy undersea warfare operations. Our study assessed the potential to predict sonic layer depth (SLD) in the western north Pacific at lead times of one to several months. We conducted correlations between SLD and remote climate system variables, and identified a high potential for skillful long-range forecasts of SLD in the western north Pacific using ... |
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| Observing System Evaluations Using GODAE Systems |
Sep-2009 |
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| Authors:
James A Cummings; Pierre-Yves Traon; Gilles Le Larnicol; Stephanie Guinehut; Yosuke Fujii; Eric Dombrowsky; Magdalena A Balmaseda; Peter R Oke; Mounir Benkiran; Matthew J Martin; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
 | Global ocean forecast systems, developed under the Global Ocean Data Assimilation Experiment (GODAE), are a powerful means of assessing the impact of different components of the Global Ocean Observing System (GOOS). Using a range of analysis tools and approaches, GODAE systems are useful for quantifying the impact of different observation types on the quality of analyses and forecasts. This assessment includes both existing and future observation platforms. Many important conclusions ... |
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| Data Assembly and Processing for Operational Oceanography: 10 Years of Achievements |
20-Jul-2009 |
27 pages |
| Authors:
Le; N Hoepffner; F Bonjean; D Griffin; G Jacobs; H Roquet; C Donlon; D Roemmich; A Bentamy; S Pouliquen; S Guinehut; G Larnicol; P Y Traon; L A Breivick; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| Data assembly and processing centers are essential elements of the operational oceanography infrastructure. They provide data and products needed by modeling and data assimilation systems; they also provide products directly useable for applications. The paper will discuss the role and functions of the data centers for operational oceanography and describe some of the main data assembly centers developed during GODAE: Argo and Coriolis data centers for in-situ data, SSALTO/DUACS and ... |
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| Turbulence Parameterization and Lateral Mixing |
30-Jun-2009 |
16 pages |
| Authors:
Eric A D'Asaro; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
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| This project funded approximately one month of salary for the PI to prepare for and participate in an ONR workshop in Alaska, planning for the field programs in 2011 and 2012 as part of the ONR Lateral Mixing DRI. Meeting expenses included airfare and per diem. At the meeting, analysis results supported by a previous ONR grant, N00014-94-1-0024 were discussed with ONR Program Managers. |
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| Climate Analysis and Long Range Forecasting of Dust Storms in Iraq |
Jun-2009 |
85 pages |
| Authors:
Jacquelyn Crook; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| Skillful long range forecasts of dust storms have the potential to be very useful in planning operations by the Department of Defense (DoD) and other organizations. Our study assessed the potential to predict Iraq dust storms at long lead times (e.g., several weeks to several months). We examined two variables that associated with dust storms: precipitation rate and surface winds. To characterize conditions during dust storms, we generated averages (conditional ... |
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| Fin Whales in the Mediterranean Sea: Habitat Identification and Oceanographic Characterization |
Jun-2009 |
12 pages |
| Authors:
Bruce R Mate; OREGON STATE UNIV CORVALLIS
|
| This project identified the seasonal distribution and movements of fin whales in the Mediterranean Sea with satellite-monitored radio tags in relation to environmental parameters: sea surface temperature, chlorophyll concentration, current movement, primary production and prey abundance in collaboration with the laboratory of Dr. Christophe Guinet. By comparing these movements with the environmental parameters, a better understanding of fin whale ecology will be possible. The telemetry information will enable collaborators to ... |
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| US GODAE: Global Ocean Prediction with the Hybrid Coordinate Ocean Model (HYCOM) |
Jun-2009 |
16 pages |
| Authors:
Rainer Bleck; Francisco Werner; Ruoying He; Robert Weisberg; Ashwanth Srinivasan; Hendrik L Tolman; Alan J Wallcraft; Peter Cornillon; E J Metzger; James A Cummings; Ole M Smedstad; Harley E Hurlburt; George R Halliwell; Eric P Chassignet; Alexander Barth; Steve Hankin; Remy Baraille; Carlos Lozano; John Wilkin; FLORIDA STATE UNIV TALLAHASSEE CENTER FOR OCEAN-ATMOSPHERIC PREDICTION STUDIES
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| During the past five to ten years, a broad partnership of institutions under NOPP sponsorship has collaborated in developing and demonstrating the performance and application of eddy-resolving, real-time global- and basin-scale ocean prediction systems using the HYbrid Coordinate Ocean Model (HYCOM). The partnership represents a broad spectrum of the oceanographic community, bringing together academia, federal agencies, and industry/commercial entities, and spanning modeling, data assimilation, data management and serving, observational capabilities, ... |
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| Coast Guard Deepwater Acquisition Programs: Background, Oversight Issues, and Options for Congress |
29-May-2009 |
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| Authors:
Ronald O'Rourke; LIBRARY OF CONGRESS WASHINGTON DC CONGRESSIONAL RESEARCH SERVICE
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| The term Deepwater refers to a collection of more than a dozen Coast Guard acquisition programs for replacing and modernizing the service?s aging fleet of deepwater-capable ships and aircraft. Until April 2007, the Coast Guard had pursued these programs as a single, integrated acquisition program that was known as the Integrated Deepwater System (IDS) program or Deepwater program for short. The now-separated Deepwater acquisition programs include plans for, among other ... |
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| Comprehensive Environmental Measurements from Autonomous Profiling Floats |
12-May-2009 |
3 pages |
| Authors:
Thomas B Sanford; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
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| The PI attended three ONR workshops to discuss and help define the future integrated observational program for the Quantifying, Predicting and Exploiting Uncertainty (QPEU), more specifically to help formulate an experiment to study the Kuroshio intrusion, nonlinear internal waves (NLIWs), internal tides, inertial waves, and turbulence mixing resulting from the Kuroshio-topography interaction. The resulting plan is briefly discussed. |
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| Monitoring Cetaceans in the North Pacific |
Apr-2009 |
18 pages |
| Authors:
Kathleen M Stafford; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
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| Two projects were undertaken to monitor cetaceans in the North Pacific. The first was designed to obtain passive acoustic data from the U.S. Navy's Northern Edge Range. Three instruments were deployed in April 2008 to monitor both high (up to 25 kHz) and low (up to 1 kHz) frequencies for odontocetes and mysticetes, respectively. Unfortunately, these instruments did not record any data. The second project was to analyze retrospective data ... |
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| Objective Estimates of Westward Rossby Wave and Eddy Propagation from Sea Surface Height Analyses |
17-Mar-2009 |
19 pages |
| Authors:
C N Barron; A B Kara; G A Jacobs; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| An objective method to estimate westward propagation of sea surface height (SSH) anomalies is introduced and compared to a subjective technique. Both approaches use time series extracted from global SSH analyses, prepared by optimal interpolation of altimeter data, as described in detail. The cost function used in the objective method calculates the mean along-slope standard deviation, where slope is the reciprocal of propagation speed and defines the angle of linear ... |
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| A Statistical-Dynamical Approach to Intraseasonal Prediction of Tropical Cyclogenesis in the Western North Pacific |
Mar-2009 |
129 pages |
| Authors:
Bryan D Mundhenk; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| We have developed a combined statistical-dynamical prediction scheme to predict the probability of tropical cyclone (TC) formation at daily, 2.5 degree horizontal resolution across the western North Pacific at intraseasonal lead times. Through examination of previous research and our own analysis, we chose five variables to represent the favorability of the climate system to support tropical cyclogenesis. These so-called large-scale environmental factors (LSEFs) include: low-level relative vorticity, sea surface temperature, ... |
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| Sea Spray Icing of Drilling and Production Platforms |
Feb-2009 |
63 pages |
| Authors:
Edgar L Andreas; Kathleen F Jones; ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB
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| Because of the observed decrease in the ice cover in the Beaufort and Chukchi Seas, it is possible that spray icing of rigs used for oil exploration and drilling may be more frequent and possibly more severe in the coming years than it has been in the past. In this report we describe a model for sea spray icing on fixed offshore structures. The accretion of small sea spray droplets ... |
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| Detection of Rossby Waves in Multi-Parameters in Multi-Mission Satellite Observations and HYCOM Simulations in the Indian Ocean |
Jan-2009 |
12 pages |
| Authors:
Jay F Shriver; Bulusu Subrahmanyam; David M Heffner; David Cromwell; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| Rossby waves are difficult to detect with in situ methods. However, as we show in this paper, they can be clearly identified in multi-parameters in multi-mission satellite observations of sea surface height (SSH), sea surface temperature (SST) and ocean color observations of chlorophyll-a (chl-a), as well as 1/12-deg global HYbrid Coordinate Ocean Model (HYCOM) simulations of SSH, SST and sea surface salinity (SSS) in the Indian Ocean. While the surface ... |
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| U. S. GODAE: Global Ocean Prediction with the HYbrid Coordinate Ocean Model |
Jan-2009 |
16 pages |
| Authors:
Harley E Hurlburt; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS
|
| Develop a next generation eddy-resolving, fully global ocean prediction system using HYCOM with 1/12 equatorial resolution. (2) Transition this system to NAVOCEANO for operational use in 2008 with assimilation of sea surface height (SSH) from satellite altimeters, sea surface temperature (SST) and temperature (T)/salinity (S) profiles and the ability to perform skillful 30-day forecasts. (3) Include two-way coupling to an ice model. (4) Ensure that an accurate and generalized ocean ... |
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| Bio-Physical Ocean Modeling in the Gulf of Mexico |
Jan-2009 |
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| Authors:
Sergio deRada; Stephanie Anderson; Robert A Arnone; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| The Naval Research Laboratory (NRL) Oceanography Division has implemented a 1/25 deg horizontal-resolution numerical ocean model for the Gulf of Mexico (GOM). The model domain encompasses the entire GOM extending from 18 deg to 31 deg North and from 77 deg to 98 deg West. The physical formulation is based on the Naval Coastal Ocean Model (NCOM) configured with a 40 level -z vertical structure: 19 terrain-following (sigma) levels at ... |
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| Blast and Fragment Protective Sandwich Panel Concepts for Stainless Steel Monohull Designs |
21-Oct-2008 |
258 pages |
| Authors:
H G Wadley; VIRGINIA UNIV CHARLOTTESVILLE OFFICE OF SPONSORED PROGRAMS
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| The prevention or mitigation of ship hull damage from underwater explosions (UNDEX) is of vital need for surface combatant Naval ships. This research program sought to devise blast and ballistic protection concepts applicable to the design and fabrication of ship hull structures using AL6XN stainless steel sandwich panel constructions, which met threat and protection levels defined by the Navy. Efforts were undertaken in two phases to design, fabricate, experimentally investigate ... |
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| Monitoring the Ocean Using High Frequency Ambient Sound |
01-Oct-2008 |
11 pages |
| Authors:
Jeffrey A Nystuen; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
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| To make passive acoustic monitoring of the marine environment an accepted quantitative tool for measuring sea surface conditions (wind speed, rainfall and sea state), monitoring for the presence and identity of marine wildlife (especially whales), and monitoring anthropogenic activities including shipping, sonar and other industrial activities. By establishing a methodology for describing the sound budget for a location, including the quasi-steady sound levels from the sea surface and the frequency ... |
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| Fast Electromagnetic Solvers for Large-Scale Naval Scattering Problems |
27-Sep-2008 |
17 pages |
| Authors:
Lawrence Carin; SIGNAL INNOVATIONS GROUP INC DURHAM NC
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| Efficient modeling of electromagnetic scattering has always been an active topic in the field of computational electromagnetics. To reduce the memory and CPU time in the method of moments (MoM) solution, an efficient method based on pseudo skeleton approximation is presented in this report. The algorithm is purely algebraic, and therefore its performance is not associated with the kernel functions in the integral equations. The algorithm starts with a multilevel ... |
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| Investigating Characteristics of Air-Sea Interactions in the Wave and Surface Layers |
02-Jul-2008 |
13 pages |
| Authors:
Jielun Sun; NATIONAL CENTER FOR ATMOSPHERIC RESEARCH BOULDER CO MESOSCALE AND MICROSCALE METEOROLOGY DIV
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| We were funded to participate in the Coupled Boundary Layers/Air-Sea Transfer under low wind (CBLAST-Low) pilot experiment in 2001 and main experiment in 2003 and analyze the data collected from both field campaigns. Our focuses are air-sea interactions under weak winds by analyzing simultaneous measurements of directional waves and atmospheric turbulence. We found that air-sea interactions strongly depend on whether the oceanic wave energy peak is dominated by swell or ... |
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| Aircraft and In Situ Salinity and Ocean Color Measurements and Comparisons in the Gulf of Mexico |
Jul-2008 |
5 pages |
| Authors:
Derek Burrage; Joel Wesson; Stephan Howden; Chris Osburn; Virgilio Maisonet; Xiagong Chen; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| We report here on aircraft measurements made in May, 2007, with the NRL STARRS (Salinity, Temperature and Roughness Remote Scanner), and optical multi-wavelength radiance and irradiance sensors (Satlantic OCR-507 at SEA- WIFS wavelength bands). These measurements were made in conjunction with in situ measurements of sea surface salinity (SSS), ocean color, and fluorescence in the Atchafalaya River outflow from the R/V Pelican. In this work we demonstrate the ability of ... |
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| Summer Generation of the Southern Gulf of California Eddy Train |
24-Jun-2008 |
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| Authors:
Luis Zamudio; Patrick J Hogan; E J Metzger; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| Ocean color and sea surface temperature satellite-observations show the existence of a series of anticyclonic eddies along the axis of the southern Gulf of California (SGOC). To investigate the summer generation of these eddies, a regional version of the HYbrid Coordinate Ocean Model (HYCOM) has been configured for the GOC and has been nested inside the global model. A Suite of experiments, using the nested GOC model, was developed and ... |
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| Indian Ocean Surface Circulations and Their Connection to Indian Ocean Dipole, Identified From Ocean Surface Currents Analysis Real Time (OSCAR) Data |
01-Jun-2008 |
91 pages |
| Authors:
Haris S Rana; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| Ocean surface circulation is an essential component of the world climate system. In this study the Ocean Surface Currents Analysis - Real Time (OSCAR) data, derived from satellite altimeter and scatterometer is used to investigate the connection between the Indian Ocean Dipole and eastward equatorial jet. The raw OSCAR data set was refined using the Optimal Spectral Decomposition method (OSD). Data was analyzed to show the seasonal variability of the ... |
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| Sinusoidal Vertical Motion of a Sonobuoy Suspension: Experimental Data and a Theoretical Model |
Jun-2008 |
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| Authors:
David M F Chapman; Dusko B A Kezele; DEFENCE RESEARCH AND DEVELOPMENT ATLANTIC DARTMOUTH (CANADA)
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| To isolate its acoustic sensor from the large vertical motions of the buoy at the ocean surface, a typical sonobuoy employs a low-pass mechanical filter comprising a bungee cord (spring) and a damper disk (hydrodynamic added mass and damping). If the system were to behave as a driven simple harmonic oscillator, the transfer function of vertical motion would roll off at 40 dB/decade above resonance; however, experimental systems of this ... |
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| 2007 Program of Study: Boundary Layers |
Jun-2008 |
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| Authors:
Claudia Cenedese; John A Whitehead; Joseph Pedlosky; Steven Lentz; WOODS HOLE OCEANOGRAPHIC INSTITUTION MA
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| The topic of the Principal Lectures for the forty-ninth year of the program was Boundary Layers. The subject centers around those problems in which the boundary conditions lead to a large gradient near the boundary. Nine of this year's principal lectures were given by Joe Pedlosky and the tenth was given by Steve Lentz. The fluid mechanics of boundary layers was reviewed, first starting from its classical roots and then ... |
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| Shallow Water Mid-Frequency Research and FY07 Experiment |
05 MAY 2008 |
7 pages |
| Authors:
Dajun Tang; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
|
| Long-term goals: To understand mid-frequency (1-10 kHz) acoustics in shallow waters through measurements and modeling, including propagation, reflection, and forward- and backscatter. The top-level goals of this effort are to understand the important environmental processes, which impact mid-frequency sonar performances in shallow water environments; and to develop means to efficiently collect those environmental data. The LEAR (Littoral Environmental Acoustics Research) acoustics field experiment, part of Shallow Water 2006 (SW06) project, ... |
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| Potential Flow Forces and Moments from Selected Ship Flow Codes in a Set of Numerical Experiments. Appendix I - Time History Plots for 2-DOF Wave Contouring Motion of Model 5613 |
May-2008 |
243 pages |
| Authors:
NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD
|
| This appendix contains all plots and tables for simulations of task 3 involving 2-DOF nominal wave contouring of Model 5613 scaled to the length 154 m. It presents results for wave contouring in both beam and following seas. In either case the vertical position of the center of gravity is always at the water surface. For condition 1, where the ship undergoes prescribed heave and pitch motions in regular following ... |
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| Potential Flow Forces and Moments from Selected Ship Flow Codes in a Set of Numerical Experiments. Appendix J - Time History Plots for 2-DOF Wave Contouring Motion of Model 5514 |
May-2008 |
243 pages |
| Authors:
NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD
|
| This appendix contains all plots and tables for the simulations of task 3 involving 2-DOF nominal wave contouring of Model 5514 scaled to the length 142 m. It presents results for wave contouring in both beam and following seas. In either case the vertical position of the center of gravity is always at the water surface. For condition 1, where the ship undergoes prescribed heave and pitch motions in regular ... |
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| Modeling the SAR Signature of Nonlinear Internal Waves |
APR 2008 |
17 pages |
| Authors:
Ellen E. Lettvin; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
|
| Nonlinear Internal Waves are pervasive globally, particularly in coastal waters. The currents and displacements associated with internal waves influence acoustic propagation and underwater navigation, as well as ocean transport and mixing. Synthetic Aperture Radar (SAR) imagery can reveal the surface manifestations of internal waves (IWs) in satellite imagery and so is routinely used to locate and characterize these features. Though some of the mechanisms that link the SAR signatures, surface ... |
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| On the Relationship Between Satellite-Estimated Bio-Optical and Thermal Properties in the Gulf of Mexico |
15 MAR 2008 |
28 pages |
| Authors:
Jason K. Jolliff; John C. Kindle; Bradley Penta; Robert Helber; ZhongPing Lee; Igor G. Shulman; Robert A. Amone; Clark D. Rowley; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS
|
| Three years of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) ocean color data were combined with three-dimensional thermal fields generated by the U.S. Navy's Modular Ocean Data Assimilation System (MODAS) in order to examine the interdependencies between bio-optical fields and their relationship to seasonal and mesoscale changes in upper ocean thermal structure. The combined data set suggests that the oceanic boundary layer within the Gulf of Mexico may be broadly defined by ... |
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| Environmental Support to Amphibious Craft, Patrol Boats, and Coastal Ships: An Annotated Bibliography |
05 MAR 2008 |
48 pages |
| Authors:
Charles M. Bachmann; Robert A. Fusina; C. R. Nichols; Jack McDermid; NAVAL RESEARCH LAB WASHINGTON DC
|
| This annotated bibliography is a selection of citations to books, articles, documents, and data bases highlighting environmental conditions that impact the safety and performance of amphibious craft, patrol boats, and ships designed for coastal operations. Each citation is followed by a brief summary and evaluation of the source (i.e., the annotation). Most annotations will define the scope of the source, list significant cross references, and identify the relevant environmental conditions. ... |
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| A Quantitative Approach to Determine Analogous Areas Using Environmental Parameters |
MAR 2008 |
159 pages |
| Authors:
Christopher L. Bryan; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The backbone of the success of the United States Naval Forces has been its ability to train for future events. By conducting successful training operations, the Navy has prepared for real-world operations. The principle, "fight like you train, train like you fight," has no less significance today than it did in the past. The purpose of this thesis is to develop a new, robust analogous area determination tool for the ... |
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| Deriving Sea Surface Salinity and Density Variations From Satellite and Aircraft Microwave Radiometer Measurements: Application to Coastal Plumes Using STARRS |
MAR 2008 |
22 pages |
| Authors:
Derek M. Burrage; Joel C. Wesson; Jerry Miller; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| Using brightness temperature Tb measurements from L-band airborne microwave radiometers, with independent sea surface temperature (SST) observations, sea surface salinity (SSS) can be remotely determined with errors of about 1 psu in temperate regions. Nonlinearities in the relationship between $Tb$, SSS, and SST produce variations in the sensitivity of salinity S to variations in Tb and SST. Despite significant efforts devoted to SSS remote sensing retrieval algorithms, little consideration has ... |
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| Performance of Mixed Layer Models in Simulating SST in the Equatorial Pacific Ocean |
23 FEB 2008 |
17 pages |
| Authors:
Birol Kara; Alan J. Wallcraft; Paul J. Martin; Eric P. Chassignet; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| This paper examines the ability of three ocean mixed layer submodels to depict inter-annual variations of sea surface temperature (SST) in a global configuration of the HYbrid Coordinate Ocean Model (HYCOM). The mixed layer submodels are (1) the K-Profile Parameterization (KPP), (2) the NASA Goddard Institute for Space Studies (GISS) turbulence closure, and (3) the Mellor-Yamada Level 2.5 (MY) turbulence closure. Accuracy of SSTs from the submodels is investigated during ... |
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| Daily Inter-Annual Simulations of SST and MLD using Atmospherically Forced OGCMs: Model Evaluation in Comparison to Buoy Time Series |
30 JAN 2008 |
26 pages |
| Authors:
A. B. Kara; Harley E. Hurlburt; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| A systematic methodology for model-data comparisons of sea surface temperature (SST) and mixed layer depth (MLD) is presented using inter-annual simulations from an ocean general circulation model (OGCM), the Naval Research Laboratory (NRL) Layered Ocean Model (NLOM), over 1980-1998. The model-data comparisons performed here are applicable to other OGCMs and are sufficiently detailed to allow easy comparison of results from other models with NLOM, including statistics at specific buoy locations ... |
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| Statistical Characteristics of the Global Surface Current Speeds Obtained from Satellite Altimetry and Scatterometer Data |
01-Jan-2008 |
17 pages |
| Authors:
Peter C Chu; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF OCEANOGRAPHY
|
| Near-real time ocean surface currents derived from satellite altimeter (JASON-1, GFO, ENVISAT) and scatterometer (QSCAT) data on 1 degree 1 degree resolution for world oceans (60 degrees S to 60 degrees N) are available online as Ocean Surface Current Analyses Real Time (OSCAR) . The probability distribution function (PDF) of the current speeds (w), constructed from global OSCAR data from 1992 to 2008, satisfies the two-parameter Weibull distribution reasonably well, ... |
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| Value of Bulk Heat Flux Parameterizations for Ocean SST Prediction |
Jan-2008 |
19 pages |
| Authors:
Eric P Chassignet; Harley E Hurlburt; Alan J Wallcraft; A B Kara; George H Halliwell; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| Bulk heat flux parameterization is an increasingly popular technique for forcing non-coupled ocean models. If sea surface temperature (SST) from the model is colder (warmer) than observed, then the net heat flux will be higher (lower) than observed; thus bulk parameterizations tend to keep model SST close to observations SST on long time scales. However, bulk parameterizations imply neither among damping of SST variability nor strong relaxation to near-surface (e.g., ... |
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| Deriving Sea Surface Salinity and Density Variations from Satellite and Aircraft Microwave Radiometer Measurements: Application to Coastal Plumes Using STARRS |
NOV 2007 |
22 pages |
| Authors:
Derek Burrage; Joel Wesson; Jerry Miller; C. Cabarro; J. Font; A. Camps; A. Piola; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| Using brightness temperature Tb measurements from L-band airborne microwave radiometers, with independent sea surface temperature (SST) observations, sea surface salinity (SSS) can be remotely determined with errors of about 1 psu in temperate regions Nonlinearities in the relationship between Tb, SSS and SST produce variations in the sensitivity of salinity S to variations in Tb and SST. Despite significant efforts devoted to SSS remote sensing retrieval algorithms, little consideration has ... |
|
| Study of the Implications of Whitecap Intermittency on the Uniform Sea-salt Aerosol Source Approximation and Deposition Velocity |
29 OCT 2007 |
91 pages |
| Authors:
William A. Hoppel; Peter F. Caffrey; NAVAL RESEARCH LAB WASHINGTON DC REMOTE SENSING DIV
|
| The source function and deposition velocity of sea-salt particles used in large-scale models assumes that the source and deposition is uniform over areas large compared to the horizontal grid spacing of the model, whereas sea-salt aerosol is overwhelmingly generated by white caps whose surface distribution is usually sparse and sporadic. The analysis presented here uses several puff plume models to study the validity of the underlying assumptions of the horizontally ... |
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| Relationships Between Global Warming and Tropical Cyclone Activity in the Western North Pacific |
SEP 2007 |
163 pages |
| Authors:
David W. Meyer; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| In this work, we investigate the relationships between global warming and tropical cyclone activity in the Western North Pacific (WNP). Our hypothesis is that global warming impacts on TC activity occur through changes in the large scale environmental factors (LSEFs) known to be important in determining the formation and intensity of TCs. The LSEFs on which we focus are: Sea surface temperature (SST) exceeding 26C Weak vertical shear in horizontal ... |
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| Cross-Shelf Circulation and Momentum and Heat Balances Over the Inner Continental Shelf Near Martha's Vineyard, Massachusetts |
SEP 2007 |
268 pages |
| Authors:
Melanie R. Fewings; MASSACHUSETTS INST OF TECH CAMBRIDGE JOINT PROGRAM IN APPLIED OCEAN SCIENCE AND ENGINEERING
|
| The water circulation and evolution of water temperature over the inner continental shelf are investigated using observations of water velocity, temperature, density, and bottom pressure; surface gravity waves; wind stress; and heat flux between the ocean and atmosphere during 2001-2007. When waves are small, cross-shelf wind stress is the dominant mechanism driving cross-shelf circulation. The along-shelf wind stress does not drive a substantial cross- shelf circulation. The response to a ... |
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| Internal Tide Generation by Steep Topography |
SEP 2007 |
5 pages |
| Authors:
Eric Kunze; Thomas Sanford; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
|
| The purpose of this proposal was to support Dr. Eric Kunze, Applied Physics Laboratory, University of Washington (now at University of Victoria) and Dr. Pascale Lelong (via a subcontract to Northwest Research Associates, Seattle, Washington) to numerically explore an alternative solution method to Baines' (1982) internal tide generation theory for arbitrary 1-D topography h(x). The solution method uses characteristic coordinates along which signals of frequency omega propagate. |
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| Full-Plane STWAVE with Bottom Friction. 2. Model Overview |
AUG 2007 |
16 pages |
| Authors:
Jane McKee Smith; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
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| The purpose of this System-Wide Water Resources (SWWRP) Technical Note is to describe the full-plane version of the STWAVE wave generation and transformation model (Smith et al. 2001; Smith 2001; Smith and Smith 2002; and Smith and Zundel 2006). |
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| Evaluation of Ocean Models Using Observed and Simulated Drifter Trajectories: Impact of Sea Surface Height on Synthetic Profiles for Data Assimilation |
17 JUL 2007 |
12 pages |
| Authors:
Charlie N. Barron; Lucy F. Smedstad; Jan M. Dastugue; Ole Martin Smedstad; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| The impact of global Navy Layered Ocean Model (NLOM) sea surface height (SSH) on global Navy Coastal Ocean Model (NCOM) nowcasts of ocean currents is investigated in a series of experiments. The studies focus on two primary aspects: the role of NLOM horizontal resolution and the role of differences between the SSH means in NLOM and the Modular Ocean Data Assimilation System (MODAS) climatology. To evaluate the impact of changes ... |
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| Spatial Averaging of Oceanic Rainfall Variability Using Underwater Sound. Ionian Sea Rainfall Experiment 2004: Acoustic Component |
JUL 2007 |
47 pages |
| Authors:
Jeffrey A. Nystuen; Eyal Amitai; Emmanuel N. Anagnostou3; Marios N. Anagnostou; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
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| An experiment to evaluate the inherent spatial averaging of the underwater acoustic signal from rainfall was conducted in the winter of 2004 in the Ionian Sea southeast of the coast of Greece. A mooring with four passive aquatic listeners (PALs) at 60, 200, 100, and 2000 m was deployed at 36.85 deg. N, 21.52 deg. E, 17 km west of a dual-polarization X-band coastal radar (XPOL) at Methoni, Greece. A ... |
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| Sea Clutter Generation and Target Detection |
JUL 2007 |
26 pages |
| Authors:
Stefano M. Canta; Danilo Erricolo; ILLINOIS UNIV AT CHICAGO CIRCLE COLL OF ENGINEERING
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| Propagation model for the electromagnetic field that accounts for the clutter and metallic objects in the sea. Computationally fast, and the complete work will include electromagnetic propagation models and vector antennas. |
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| Quadrifilar Helical Antenna Array for Line-of-Sight Communications Above the Ocean Surface |
25 JUN 2007 |
76 pages |
| Authors:
Michael J. Josypenko; John P. Casey; Stephen M. Davis; NAVAL UNDERSEA WARFARE CENTER DIV NEWPORT RI
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| This report describes the development of a linear array consisting of four quadrifilar helical antennas (QHAs) that is mounted on a buoy to support transmit and receive communications at 2.45 GHz along line-of-sight (LOS) paths above a sea water half-space. The array elements are designed to be immune to the multipath interference created by reflections of an incident signal from the surface of the ocean. A novel feed design for ... |
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OCEAN SURFACE
