Comparison of Various Spectral Models for the Prediction of the 100-Year Design Wave Height
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NANOOS Asset List 1 National Oceanic and Atmospheric
NANOOS Asset List 2008 NANOOS Asset List 1 National Oceanic and Atmospheric Administration 1.1 The CoastWatch West Coast Regional Node http://coastwatch.pfel.noaa.gov Daily – Monthly composites of satellite observations Sea Surface Temperature (GOES & POES) Ocean Color (MODIS and SeaWiFS) Ocean Winds (QuikSCAT) 1.2 The National Data Buoy Center http://seaboard.ndbc.noaa.gov/maps/Northwest.shtml 6 Minute – Hourly buoy observations Meteorological Observations (Air Temp., Pressure, Wind Speed and Direction) Ocean Observations (Water Temp., Wave Height, Period and Direction) 1.3 The Center for Operational Oceanographic Products and Services http://tidesandcurrents.noaa.gov http://opendap.co-ops.nos.noaa.gov/content 6 Minute near-shore station observations Meteorological Observations (Air Temp., Pressure, Wind Speed and Direction) Ocean Observations (Water Temp., Water Level) 1.4 NOAAWatch http://www.noaawatch.gov Information related to ongoing environmental events NOAAWatch themes include Air Quality, Droughts, Earthquakes, Excessive Heat, Fire, Flooding, Harmful Algal Blooms (HABs), Oil Spills, Rip Currents, Severe Weather, Space Weather, Tsunamis, and Volcanoes 1.5 National Weather Service http://www.weather.gov Environmental observations and forecasts Coastal and Marine Forecasts Weather Warnings 1 NANOOS Asset List 2008 Surface Pressure Maps Coastal and Marine Observations (Wind, Visibility, Sky Conditions, Temperature, Dew Point, Relative Humidity, Atmospheric Pressure, Pressure tendency) GOES Satellite Observations (Visible, -
Part II-1 Water Wave Mechanics
Chapter 1 EM 1110-2-1100 WATER WAVE MECHANICS (Part II) 1 August 2008 (Change 2) Table of Contents Page II-1-1. Introduction ............................................................II-1-1 II-1-2. Regular Waves .........................................................II-1-3 a. Introduction ...........................................................II-1-3 b. Definition of wave parameters .............................................II-1-4 c. Linear wave theory ......................................................II-1-5 (1) Introduction .......................................................II-1-5 (2) Wave celerity, length, and period.......................................II-1-6 (3) The sinusoidal wave profile...........................................II-1-9 (4) Some useful functions ...............................................II-1-9 (5) Local fluid velocities and accelerations .................................II-1-12 (6) Water particle displacements .........................................II-1-13 (7) Subsurface pressure ................................................II-1-21 (8) Group velocity ....................................................II-1-22 (9) Wave energy and power.............................................II-1-26 (10)Summary of linear wave theory.......................................II-1-29 d. Nonlinear wave theories .................................................II-1-30 (1) Introduction ......................................................II-1-30 (2) Stokes finite-amplitude wave theory ...................................II-1-32 -
Title Relation Between Wave Characteristics of Cnoidal Wave
Relation between Wave Characteristics of Cnoidal Wave Title Theory Derived by Laitone and by Chappelear Author(s) YAMAGUCHI, Masataka; TSUCHIYA, Yoshito Bulletin of the Disaster Prevention Research Institute (1974), Citation 24(3): 217-231 Issue Date 1974-09 URL http://hdl.handle.net/2433/124843 Right Type Departmental Bulletin Paper Textversion publisher Kyoto University Bull. Disas. Prey. Res. Inst., Kyoto Univ., Vol. 24, Part 3, No. 225,September, 1974 217 Relation between Wave Characteristics of Cnoidal Wave Theory Derived by Laitone and by Chappelear By Masataka YAMAGUCHIand Yoshito TSUCHIYA (Manuscriptreceived October5, 1974) Abstract This paper presents the relation between wave characteristicsof the secondorder approxi- mate solutionof the cnoidal wave theory derived by Laitone and by Chappelear. If the expansionparameters Lo and L3in the Chappeleartheory are expanded in a series of the ratio of wave height to water depth and the expressionsfor wave characteristics of the secondorder approximatesolution of the cnoidalwave theory by Chappelearare rewritten in a series form to the second order of the ratio, the expressions for wave characteristics of the cnoidalwave theory derived by Chappelearagree exactly with the ones by Laitone, whichare convertedfrom the depth below the wave trough to the mean water depth. The limitingarea betweenthese theories for practical applicationis proposed,based on numerical comparison. In addition, somewave characteristicssuch as wave energy, energy flux in the cnoidal waves and so on are calculated. 1. Introduction In recent years, the various higher order solutions of finite amplitude waves based on the perturbation method have been extended with the progress of wave theories. For example, systematic deviations of the cnoidal wave theory, which is a nonlinear shallow water wave theory, have been made by Kellern, Laitone2), and Chappelears> respectively. -
Sea State in Marine Safety Information Present State, Future Prospects
Sea State in Marine Safety Information Present State, future prospects Henri SAVINA – Jean-Michel LEFEVRE Météo-France Rogue Waves 2004, Brest 20-22 October 2004 JCOMM Joint WMO/IOC Commission for Oceanography and Marine Meteorology The future of Operational Oceanography Intergovernmental body of technical experts in the field of oceanography and marine meteorology, with a mandate to prepare both regulatory (what Member States shall do) and guidance (what Member States should do) material. TheThe visionvision ofof JCOMMJCOMM Integrated ocean observing system Integrated data management State-of-the-art technologies and capabilities New products and services User responsiveness and interaction Involvement of all maritime countries JCOMM structure Terms of Reference Expert Team on Maritime Safety Services • Monitor / review operations of marine broadcast systems, including GMDSS and others for vessels not covered by the SOLAS convention •Monitor / review technical and service quality standards for meteo and oceano MSI, particularly for the GMDSS, and provide assistance and support to Member States • Ensure feedback from users is obtained through appropriate channels and applied to improve the relevance, effectiveness and quality of services • Ensure effective coordination and cooperation with organizations, bodies and Member States on maritime safety issues • Propose actions as appropriate to meet requirements for international coordination of meteorological and related communication services • Provide advice to the SCG and other Groups of JCOMM on issues related to MSS Chair selected by Commission. OPEN membership, including representatives of the Issuing Services for GMDSS, of IMO, IHO, ICS, IMSO, and other user groups GMDSS Global Maritime Distress & Safety System Defined by IMO for the provision of MSI and the coordination of SAR alerts on a global basis. -
Sea State Effect on the Sea Surface Emissivity at L-Band
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by UPCommons. Portal del coneixement obert de la UPC IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 41, NO. 10, OCTOBER 2003 2307 Sea State Effect on the Sea Surface Emissivity at L-Band Jorge José Miranda, Mercè Vall-llossera, Member, IEEE, Adriano Camps, Senior Member, IEEE, Núria Duffo, Member, IEEE, Ignasi Corbella, Member, IEEE, and Jacqueline Etcheto Abstract—In May 1999, the European Space Agency (ESA) temperature images will provide looks of the same pixel under selected the Earth Explorer Opportunity Soil Moisture and incidence angles from 0 to almost 65 , which requires the Ocean Salinity (SMOS) mission to obtain global and frequent soil development of soil and sea emission models in the whole moisture and ocean salinity maps. SMOS single payload is the Microwave Imaging Radiometer by Aperture Synthesis (MIRAS), range of incidence angles, and suitable geophysical parameters an L-band two-dimensional aperture synthesis radiometer with retrieval algorithms. multiangular observation capabilities. At L-band, the brightness The dielectric permittivity for seawater is determined, among temperature sensitivity to the sea surface salinity (SSS) is low, other variables, by salinity. Therefore, in principle, it is possible approximately 0.5 K/psu at 20 C, decreasing to 0.25 K/psu at to retrieve SSS from passive microwave measurements as long 0 C, comparable to that to the wind speed 0.2 K/(m/s) at nadir. However, at a given time, the sea state does not depend only as the variables influencing the brightness temperature (TB) on local winds, but on the local wind history and the presence signal (sea surface temperature, roughness, and foam) can be of waves traveling from far distances. -
Marine Forecasting at TAFB [email protected]
Marine Forecasting at TAFB [email protected] 1 Waves 101 Concepts and basic equations 2 Have an overall understanding of the wave forecasting challenge • Wave growth • Wave spectra • Swell propagation • Swell decay • Deep water waves • Shallow water waves 3 Wave Concepts • Waves form by the stress induced on the ocean surface by physical wind contact with water • Begin with capillary waves with gradual growth dependent on conditions • Wave decay process begins immediately as waves exit wind generation area…a.k.a. “fetch” area 4 5 Wave Growth There are three basic components to wave growth: • Wind speed • Fetch length • Duration Wave growth is limited by either fetch length or duration 6 Fully Developed Sea • When wave growth has reached a maximum height for a given wind speed, fetch and duration of wind. • A sea for which the input of energy to the waves from the local wind is in balance with the transfer of energy among the different wave components, and with the dissipation of energy by wave breaking - AMS. 7 Fetches 8 Dynamic Fetch 9 Wave Growth Nomogram 10 Calculate Wave H and T • What can we determine for wave characteristics from the following scenario? • 40 kt wind blows for 24 hours across a 150 nm fetch area? • Using the wave nomogram – start on left vertical axis at 40 kt • Move forward in time to the right until you reach either 24 hours or 150 nm of fetch • What is limiting factor? Fetch length or time? • Nomogram yields 18.7 ft @ 9.6 sec 11 Wave Growth Nomogram 12 Wave Dimensions • C=Wave Celerity • L=Wave Length • -
Spectral Analysis
Ocean Environment Sep. 2014 Kwang Hyo Jung, Ph.D Assistant Professor Dept. of Naval Architecture & Ocean Engineering Pusan National University Introduction Project Phase and Functions Appraise Screen new development development Identify Commence basic Complete detail development options options & define Design & define design & opportunity & Data acquisition base case equipment & material place order LLE Final Investment Field Feasibility Decision Const. and Development Pre-FEED FEED Detail Eng. Procurement Study Installation Planning (3 - 5 M) (6 - 8 M) (33 - 36 M) 1st Production 45/40 Tendering for FEED Tendering for EPCI Single Source 30/25 (4 - 6 M) (11 - 15 M) Design Competition 20/15 15/10 0 - 10/- 5 - 15/-10 - 25/-15 Cost Estimate Accuracy (%) EstimateAccuracy Cost - 40/- 25 Equipment Bills of Material & Concept options Process systems & Material Purchase order & Process blocks defined Definition information Ocean Water Properties Density, Viscosity, Salinity and Temperature Temperature • The largest thermocline occurs near the water surface. • The temperature of water is the highest at the surface and decays down to nearly constant value just above 0 at a depth below 1000 m. • This decay is much faster in the colder polar region compared to the tropical region and varies between the winter and summer seasons. Salinity • The variation of salinity is less profound, except near the coastal region. • The river run-off introduces enough fresh water in circulation near the coast producing a variable horizontal as well as vertical salinity. • In the open sea. the salinity is less variable having an average value of about 35 ‰ (permille, parts per thousand). Viscosity • The dynamic viscosity may be obtained by multiplying the viscosity with mass density. -
Waves and Structures
WAVES AND STRUCTURES By Dr M C Deo Professor of Civil Engineering Indian Institute of Technology Bombay Powai, Mumbai 400 076 Contact: [email protected]; (+91) 22 2572 2377 (Please refer as follows, if you use any part of this book: Deo M C (2013): Waves and Structures, http://www.civil.iitb.ac.in/~mcdeo/waves.html) (Suggestions to improve/modify contents are welcome) 1 Content Chapter 1: Introduction 4 Chapter 2: Wave Theories 18 Chapter 3: Random Waves 47 Chapter 4: Wave Propagation 80 Chapter 5: Numerical Modeling of Waves 110 Chapter 6: Design Water Depth 115 Chapter 7: Wave Forces on Shore-Based Structures 132 Chapter 8: Wave Force On Small Diameter Members 150 Chapter 9: Maximum Wave Force on the Entire Structure 173 Chapter 10: Wave Forces on Large Diameter Members 187 Chapter 11: Spectral and Statistical Analysis of Wave Forces 209 Chapter 12: Wave Run Up 221 Chapter 13: Pipeline Hydrodynamics 234 Chapter 14: Statics of Floating Bodies 241 Chapter 15: Vibrations 268 Chapter 16: Motions of Freely Floating Bodies 283 Chapter 17: Motion Response of Compliant Structures 315 2 Notations 338 References 342 3 CHAPTER 1 INTRODUCTION 1.1 Introduction The knowledge of magnitude and behavior of ocean waves at site is an essential prerequisite for almost all activities in the ocean including planning, design, construction and operation related to harbor, coastal and structures. The waves of major concern to a harbor engineer are generated by the action of wind. The wind creates a disturbance in the sea which is restored to its calm equilibrium position by the action of gravity and hence resulting waves are called wind generated gravity waves. -
Variational of Surface Gravity Waves Over Bathymetry BOUSSINESQ
Gert Klopman Variational BOUSSINESQ modelling of surface gravity waves over bathymetry VARIATIONAL BOUSSINESQ MODELLING OF SURFACE GRAVITY WAVES OVER BATHYMETRY Gert Klopman The research presented in this thesis has been performed within the group of Applied Analysis and Mathematical Physics (AAMP), Department of Applied Mathematics, Uni- versity of Twente, PO Box 217, 7500 AE Enschede, The Netherlands. Copyright c 2010 by Gert Klopman, Zwolle, The Netherlands. Cover design by Esther Ris, www.e-riswerk.nl Printed by W¨ohrmann Print Service, Zutphen, The Netherlands. ISBN 978-90-365-3037-8 DOI 10.3990/1.9789036530378 VARIATIONAL BOUSSINESQ MODELLING OF SURFACE GRAVITY WAVES OVER BATHYMETRY PROEFSCHRIFT ter verkrijging van de graad van doctor aan de Universiteit Twente, op gezag van de rector magnificus, prof. dr. H. Brinksma, volgens besluit van het College voor Promoties in het openbaar te verdedigen op donderdag 27 mei 2010 om 13.15 uur door Gerrit Klopman geboren op 25 februari 1957 te Winschoten Dit proefschrift is goedgekeurd door de promotor prof. dr. ir. E.W.C. van Groesen Aan mijn moeder Contents Samenvatting vii Summary ix Acknowledgements x 1 Introduction 1 1.1 General .................................. 1 1.2 Variational principles for water waves . ... 4 1.3 Presentcontributions........................... 6 1.3.1 Motivation ............................ 6 1.3.2 Variational Boussinesq-type model for one shape function .. 7 1.3.3 Dispersionrelationforlinearwaves . 10 1.3.4 Linearwaveshoaling. 11 1.3.5 Linearwavereflectionbybathymetry . 12 1.3.6 Numerical modelling and verification . 14 1.4 Context .................................. 16 1.4.1 Exactlinearfrequencydispersion . 17 1.4.2 Frequency dispersion approximations . 18 1.5 Outline ................................. -
Air-Sea Interaction and Surface Waves
712 Air-Sea Interaction and Surface Waves Peter A.E.M. Janssen, Øyvind Breivik, Kristian Mogensen, Frédéric Vitart, Magdalena Balmaseda, Jean-Raymond Bidlot, Sarah Keeley, Martin Leutbecher, Linus Magnusson, and Franco Molteni. Research Department November 2013 Series: ECMWF Technical Memoranda A full list of ECMWF Publications can be found on our web site under: http://www.ecmwf.int/publications/ Contact: [email protected] ©Copyright 2013 European Centre for Medium-Range Weather Forecasts Shinfield Park, Reading, RG2 9AX, England Literary and scientific copyrights belong to ECMWF and are reserved in all countries. This publication is not to be reprinted or translated in whole or in part without the written permission of the Director- General. Appropriate non-commercial use will normally be granted under the condition that reference is made to ECMWF. The information within this publication is given in good faith and considered to be true, but ECMWF accepts no liability for error, omission and for loss or damage arising from its use. Air-Sea Interaction and Surface Waves 1 Introduction Presently we are developing a coupled earth system model that allows for efficient, sequential interaction of the ocean/sea-ice, atmosphere and ocean waves components, and, therefore it becomes feasible to introduce sea state effects on the upper ocean mixing and dynamics (Mogensen et al., 2012). By the end of 2013, a first version of this system will be introduced in operations in the medium-range/monthly ensemble forecasting system. The main purpose of this operational change is that coupling between atmosphere and ocean is switched on from initial time, rather than from day 9-10 in the forecast. -
6 Water Waves 35 6 Water Waves
6 WATER WAVES 35 6 WATER WAVES Surface waves in water are a superb example of a stationary and ergodic random process. The model of waves as a nearly linear superposition of harmonic components, at random phase, is confirmed by measurements at sea, as well as by the linear theory of waves, the subject of this section. We will skip some elements of fluid mechanics where appropriate, and move quickly to the cases of two-dimensional, inviscid and irrotational flow. These are the major assumptions that enable the linear wave model. 6.1 Constitutive and Governing Relations First, we know that near the sea surface, water can be considered as incompressible, and that the density ½ is nearly uniform. In this case, a simple form of conservation of mass will hold: @u @v @w + + = 0; @x @y @z where the Cartesian space is [x; y; z], with respective particle velocity vectors [u; v; w]. In words, the above equation says that net flow into a differential volume has to equal net flow out of it. Considering a box of dimensions [±x; ±y; ±z], we see that any ±u across the x-dimension, has to be accounted for by ±v and ±w: ±u±y±z + ±v±x±z + ±w±x±y = 0: w + Gw v + Gv Gy z y Gx u u + Gu x Gz v w Next, we invoke Newton’s law, in the three directions: " # " # @u @u @u @u @p @2u @2u @2u ½ + u + v + w = ¡ + ¹ + + ; @t @x @y @z @x @x2 @y2 @z2 " # " # @v @v @v @v @p @2v @2v @2v ½ + v + w + u = ¡ + ¹ + + ; @t @x @y @z @y @x2 @y2 @z2 " # " # @w @w @w @w @p @2w @2w @2w ½ + w + u + v = ¡ + ¹ + + ¡ ½g: @t @x @y @z @z @x2 @y2 @z2 6 WATER WAVES 36 Here the left-hand side of each equation is the acceleration of the fluid particle, as it moves @u through the differential volume. -
Realistic Simulation of Ocean Surface Using Wave Spectra Jocelyn Fréchot
Realistic simulation of ocean surface using wave spectra Jocelyn Fréchot To cite this version: Jocelyn Fréchot. Realistic simulation of ocean surface using wave spectra. Proceedings of the First International Conference on Computer Graphics Theory and Applications (GRAPP 2006), 2006, Por- tugal. pp.76–83. hal-00307938 HAL Id: hal-00307938 https://hal.archives-ouvertes.fr/hal-00307938 Submitted on 29 Jul 2008 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. REALISTIC SIMULATION OF OCEAN SURFACE USING WAVE SPECTRA Jocelyn Frechot´ LaBRI - Laboratoire bordelais de recherche en informatique Domaine universitaire, 351 cours de la Liber´ ation, 33405 Talence CEDEX, France [email protected] Keywords: Natural phenomena, realistic ocean waves, procedural animation, parametric energy spectra Abstract: We present a method to simulate ocean surfaces away from the coast, with correct statistical wave height and direction distributions. By using classical oceanographic parametric wave spectra, our results fit real world measurements, without depending on them. Since wave spectra are independent of the ocean model, Gerstner parametric equations and Fourier transform method can be used with them. Moreover, since they are simple to use and need very few parameters, they allow easy production of ocean surface animations usable in movies and games.