Dynamics and Mixing in the Upper Ocean Layer
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Basic Concepts in Oceanography
Chapter 1 XA0101461 BASIC CONCEPTS IN OCEANOGRAPHY L.F. SMALL College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, United States of America Abstract Basic concepts in oceanography include major wind patterns that drive ocean currents, and the effects that the earth's rotation, positions of land masses, and temperature and salinity have on oceanic circulation and hence global distribution of radioactivity. Special attention is given to coastal and near-coastal processes such as upwelling, tidal effects, and small-scale processes, as radionuclide distributions are currently most associated with coastal regions. 1.1. INTRODUCTION Introductory information on ocean currents, on ocean and coastal processes, and on major systems that drive the ocean currents are important to an understanding of the temporal and spatial distributions of radionuclides in the world ocean. 1.2. GLOBAL PROCESSES 1.2.1 Global Wind Patterns and Ocean Currents The wind systems that drive aerosols and atmospheric radioactivity around the globe eventually deposit a lot of those materials in the oceans or in rivers. The winds also are largely responsible for driving the surface circulation of the world ocean, and thus help redistribute materials over the ocean's surface. The major wind systems are the Trade Winds in equatorial latitudes, and the Westerly Wind Systems that drive circulation in the north and south temperate and sub-polar regions (Fig. 1). It is no surprise that major circulations of surface currents have basically the same patterns as the winds that drive them (Fig. 2). Note that the Trade Wind System drives an Equatorial Current-Countercurrent system, for example. -
Chapter 14. Northern Shelf Region
Chapter 14. Northern Shelf Region Queen Charlotte Sound, Hecate Strait, and Dixon canoes were almost as long as the ships of the early Spanish, Entrance form a continuous coastal seaway over the conti- and British explorers. The Haida also were gifted carvers nental shelfofthe Canadian west coast (Fig. 14.1). Except and produced a volume of art work which, like that of the for the broad lowlands along the northwest side ofHecate mainland tribes of the Kwaluutl and Tsimshian, is only Strait, the region is typified by a highly broken shoreline now becoming appreciated by the general public. of islands, isolated shoals, and countless embayments The first Europeans to sail the west coast of British which, during the last ice age, were covered by glaciers Columbia were Spaniards. Under the command of Juan that spread seaward from the mountainous terrain of the Perez they reached the vicinity of the Queen Charlotte mainland coast and the Queen Charlotte Islands. The Islands in 1774 before returning to a landfall at Nootka irregular countenance of the seaway is mirrored by its Sound on Vancouver Island. Quadra followed in 1775, bathymetry as re-entrant troughs cut landward between but it was not until after Cook’s voyage of 1778 with the shallow banks and broad shoals and extend into Hecate Resolution and Discovery that the white man, or “Yets- Strait from northern Graham Island. From an haida” (iron men) as the Haida called them, began to oceanographic point of view it is a hybrid region, similar explore in earnest the northern coastal waters. During his in many respects to the offshore waters but considerably sojourn at Nootka that year Cook had received a number modified by estuarine processes characteristic of the of soft, luxuriant sea otter furs which, after his death in protected inland coastal waters. -
A Numerical Study of the Long- and Short-Term Temperature Variability and Thermal Circulation in the North Sea
JANUARY 2003 LUYTEN ET AL. 37 A Numerical Study of the Long- and Short-Term Temperature Variability and Thermal Circulation in the North Sea PATRICK J. LUYTEN Management Unit of the Mathematical Models, Brussels, Belgium JOHN E. JONES AND ROGER PROCTOR Proudman Oceanographic Laboratory, Bidston, United Kingdom (Manuscript received 3 January 2001, in ®nal form 4 April 2002) ABSTRACT A three-dimensional numerical study is presented of the seasonal, semimonthly, and tidal-inertial cycles of temperature and density-driven circulation within the North Sea. The simulations are conducted using realistic forcing data and are compared with the 1989 data of the North Sea Project. Sensitivity experiments are performed to test the physical and numerical impact of the heat ¯ux parameterizations, turbulence scheme, and advective transport. Parameterizations of the surface ¯uxes with the Monin±Obukhov similarity theory provide a relaxation mechanism and can partially explain the previously obtained overestimate of the depth mean temperatures in summer. Temperature strati®cation and thermocline depth are reasonably predicted using a variant of the Mellor±Yamada turbulence closure with limiting conditions for turbulence variables. The results question the common view to adopt a tuned background scheme for internal wave mixing. Two mechanisms are discussed that describe the feedback of the turbulence scheme on the surface forcing and the baroclinic circulation, generated at the tidal mixing fronts. First, an increased vertical mixing increases the depth mean temperature in summer through the surface heat ¯ux, with a restoring mechanism acting during autumn. Second, the magnitude and horizontal shear of the density ¯ow are reduced in response to a higher mixing rate. -
Dynamic Behaviour of Hydraulic Structures, Part B
Dynamic behaviour of hydraulic structures Part B Structures in waves P.A. Kolkman T.H.G. Jongeling Delft Hydraulics The three manuscripts (parts A, B and C) were put in book form by Rijkswaterstaat in Dutch in a limited edition and distributed within Rijkswaterstaat and Delft Hydraulics. Dutch title of that edition is: Dynamisch gedrag van Waterbouwkundige Constructies. Ten years after this Dutch version Delft Hydraulics decided to translate the books into English thus making these available for English speaking colleagues as well. Because of in the text often referred is to Delft Hydraulic reports made for clients (so with restrictions for others to look at) we decided to limit the circulation of the English version as well. However, the books are of value also without perusal of these reports. The task was carried out by Mr. R.J. de Jong of Delft Hydraulics. Translation services were provided by Veritaal (www.veritaal.nl). Delft Hydraulics 2007 Delft Hydraulics Table of contents Part B List of symbols Part B 1 INTRODUCTION..............................................................................................................1 2 WAVES..............................................................................................................................3 2.1 Wave phenomena......................................................................................................3 2.2 Wind-generated waves .............................................................................................5 2.2.1 Wave characteristics...........................................................................................5 -
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 -
World Ocean Thermocline Weakening and Isothermal Layer Warming
applied sciences Article World Ocean Thermocline Weakening and Isothermal Layer Warming Peter C. Chu * and Chenwu Fan Naval Ocean Analysis and Prediction Laboratory, Department of Oceanography, Naval Postgraduate School, Monterey, CA 93943, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-831-656-3688 Received: 30 September 2020; Accepted: 13 November 2020; Published: 19 November 2020 Abstract: This paper identifies world thermocline weakening and provides an improved estimate of upper ocean warming through replacement of the upper layer with the fixed depth range by the isothermal layer, because the upper ocean isothermal layer (as a whole) exchanges heat with the atmosphere and the deep layer. Thermocline gradient, heat flux across the air–ocean interface, and horizontal heat advection determine the heat stored in the isothermal layer. Among the three processes, the effect of the thermocline gradient clearly shows up when we use the isothermal layer heat content, but it is otherwise when we use the heat content with the fixed depth ranges such as 0–300 m, 0–400 m, 0–700 m, 0–750 m, and 0–2000 m. A strong thermocline gradient exhibits the downward heat transfer from the isothermal layer (non-polar regions), makes the isothermal layer thin, and causes less heat to be stored in it. On the other hand, a weak thermocline gradient makes the isothermal layer thick, and causes more heat to be stored in it. In addition, the uncertainty in estimating upper ocean heat content and warming trends using uncertain fixed depth ranges (0–300 m, 0–400 m, 0–700 m, 0–750 m, or 0–2000 m) will be eliminated by using the isothermal layer. -
Waves and Weather
Waves and Weather 1. Where do waves come from? 2. What storms produce good surfing waves? 3. Where do these storms frequently form? 4. Where are the good areas for receiving swells? Where do waves come from? ==> Wind! Any two fluids (with different density) moving at different speeds can produce waves. In our case, air is one fluid and the water is the other. • Start with perfectly glassy conditions (no waves) and no wind. • As wind starts, will first get very small capillary waves (ripples). • Once ripples form, now wind can push against the surface and waves can grow faster. Within Wave Source Region: - all wavelengths and heights mixed together - looks like washing machine ("Victory at Sea") But this is what we want our surfing waves to look like: How do we get from this To this ???? DISPERSION !! In deep water, wave speed (celerity) c= gT/2π Long period waves travel faster. Short period waves travel slower Waves begin to separate as they move away from generation area ===> This is Dispersion How Big Will the Waves Get? Height and Period of waves depends primarily on: - Wind speed - Duration (how long the wind blows over the waves) - Fetch (distance that wind blows over the waves) "SMB" Tables How Big Will the Waves Get? Assume Duration = 24 hours Fetch Length = 500 miles Significant Significant Wind Speed Wave Height Wave Period 10 mph 2 ft 3.5 sec 20 mph 6 ft 5.5 sec 30 mph 12 ft 7.5 sec 40 mph 19 ft 10.0 sec 50 mph 27 ft 11.5 sec 60 mph 35 ft 13.0 sec Wave height will decay as waves move away from source region!!! Map of Mean Wind -
USER MANUAL SWASH Version 7.01
SWASH USER MANUAL SWASH version 7.01 SWASH USER MANUAL by : TheSWASHteam mail address : Delft University of Technology Faculty of Civil Engineering and Geosciences Environmental Fluid Mechanics Section P.O. Box 5048 2600 GA Delft The Netherlands website : http://www.tudelft.nl/swash Copyright (c) 2010-2020 Delft University of Technology. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back- Cover Texts. A copy of the license is available at http://www.gnu.org/licenses/fdl.html#TOC1. iv Contents 1 About this manual 1 2 Generaldescriptionandinstructionsforuse 3 2.1 Introduction................................... 3 2.2 Background,featuresandapplications . ...... 3 2.2.1 Objectiveandcontext ......................... 3 2.2.2 Abird’s-eyeviewofSWASH. 4 2.2.3 ModelfeaturesandvalidityofSWASH . 7 2.2.4 Relation to Boussinesq-type wave models . .... 8 2.2.5 Relation to circulation and coastal flow models. ...... 9 2.3 Internal scenarios, shortcomings and coding bugs . ......... 9 2.4 Unitsandcoordinatesystems . 10 2.5 Choiceofgridsandtimewindows . .. 11 2.5.1 Introduction............................... 11 2.5.2 Computationalgridandtimewindow . 12 2.5.3 Inputgrid(s)andtimewindow(s) . 13 2.5.4 Input grid(s) for transport of constituents . ...... 14 2.5.5 Outputgrids .............................. 15 2.6 Boundaryconditions .............................. 16 2.7 Timeanddatenotation ............................ 17 2.8 Troubleshooting................................. 17 3 Input and output files 19 3.1 General ..................................... 19 3.2 Input/outputfacilities . .. 19 3.3 Printfileanderrormessages . .. 20 4 Description of commands 21 4.1 Listofavailablecommands. -
Introduction to Oceanography
Introduction to Oceanography Introduction to Oceanography Lecture 14: Tides, Biological Productivity Memorial Day holiday Monday no lab meetings Go to any other lab section this week (and let the TA know!) Bay of Fundy -- low tide, Photo by Dylan Kereluk, . Creative Commons A 2.0 Generic, Mudskipper (Periophthalmus modestus) at low tide, photo by OpenCage, Wikimedia Commons, Creative http://commons.wikimedia.org/wiki/File:Bay_of_Fundy_-_Tide_Out.jpg Commons A S-A 2.5, http://commons.wikimedia.org/wiki/File:Periophthalmus_modestus.jpg Tides Earth-Moon-Sun System Planet-length waves Cyclic, repeating rise & fall of sea level • Earth-Sun Distance – Most regular phenomenon in the oceans 150,000,000 km Daily tidal variation has great effects on life in & around the ocean (Lab 8) • Earth-Moon Distance 385,000 km Caused by gravity and Much closer to Earth, but between Earth, Moon & much less massive Sun, their orbits around • Earth Obliquity = 23.5 each other, and the degrees Earth’s daily spin – Seasons Photos by Samuel Wantman, Creative Commons A S-A 3.0, http://en.wikipedia.org/ wiki/File:Bay_of_Fundy_Low_Tide.jpg and Figure by Homonculus 2/Geologician, Wikimedia Commons, http://en.wikipedia.org/wiki/ Creative Commons A 3.0, http://en.wikipedia.org/wiki/ File:Bay_of_Fundy_High_Tide.jpg File:Lunar_perturbation.jpg Tides are caused by the gravity of the Moon and Sun acting on Scaled image of Earth-Moon distance, Nickshanks, Wikimedia Commons, Creative Commons A 2.5 Earth and its ocean. Pluto-Charon mutual orbit, Zhatt, Wikimedia Commons, Public -
Microbial Community and Geochemical Analyses of Trans-Trench Sediments for Understanding the Roles of Hadal Environments
The ISME Journal (2020) 14:740–756 https://doi.org/10.1038/s41396-019-0564-z ARTICLE Microbial community and geochemical analyses of trans-trench sediments for understanding the roles of hadal environments 1 2 3,4,9 2 2,10 2 Satoshi Hiraoka ● Miho Hirai ● Yohei Matsui ● Akiko Makabe ● Hiroaki Minegishi ● Miwako Tsuda ● 3 5 5,6 7 8 2 Juliarni ● Eugenio Rastelli ● Roberto Danovaro ● Cinzia Corinaldesi ● Tomo Kitahashi ● Eiji Tasumi ● 2 2 2 1 Manabu Nishizawa ● Ken Takai ● Hidetaka Nomaki ● Takuro Nunoura Received: 9 August 2019 / Revised: 20 November 2019 / Accepted: 28 November 2019 / Published online: 11 December 2019 © The Author(s) 2019. This article is published with open access Abstract Hadal trench bottom (>6000 m below sea level) sediments harbor higher microbial cell abundance compared with adjacent abyssal plain sediments. This is supported by the accumulation of sedimentary organic matter (OM), facilitated by trench topography. However, the distribution of benthic microbes in different trench systems has not been well explored yet. Here, we carried out small subunit ribosomal RNA gene tag sequencing for 92 sediment subsamples of seven abyssal and seven hadal sediment cores collected from three trench regions in the northwest Pacific Ocean: the Japan, Izu-Ogasawara, and fi 1234567890();,: 1234567890();,: Mariana Trenches. Tag-sequencing analyses showed speci c distribution patterns of several phyla associated with oxygen and nitrate. The community structure was distinct between abyssal and hadal sediments, following geographic locations and factors represented by sediment depth. Co-occurrence network revealed six potential prokaryotic consortia that covaried across regions. Our results further support that the OM cycle is driven by hadal currents and/or rapid burial shapes microbial community structures at trench bottom sites, in addition to vertical deposition from the surface ocean. -
Manuels Et Guides 14 Commission Océanographique Intergouvernementale
Manuels et guides 14 Commission océanographique intergouvernementale Manuel sur la mesure et l’interprétation du niveau de la mer Marégraphes radar VolumeV Organisation Commission des Nations Unies océanographique pour l’éducation, intergouvernementale la science et la culture Commission océanographique intergouvernementale Organisation des Nations unies pour l’éducation, la science et la culture 7, place de Fontenoy 75352 Paris 07 SP, France Tel: +33 1 45 68 10 10 Fax: +33 1 45 68 58 12 Website: http://ioc.unesco.org JCOMM Technical Report No. 89 Manuels et guides 14 Commission océanographique intergouvernementale Manuel sur la mesure et l’interprétation du niveau de la mer Marégraphes radar VolumeV UNESCO 2016 Les appellations employées dans cette publication et la présentation des données qui y figurent n’impliquent de la part des secrétariats de l’UNESCO et de la COI aucune prise de position quant au statut juridique des pays ou territoire, ou de leurs autorités, ni quant au tracé de leurs frontières. Équipe de rédaction : Directeur : Philip L. Woodworth (NOC, Royaume-Uni) Thorkild Aarup (COI, UNESCO) Gaël André, Vincent Donato et Séverine Enet (SHOM, France) Richard Edwing et Robert Heitsenrether (NOAA, États-Unis) Ruth Farre (SAHNO, Afrique du Sud) Juan Fierro et Jorge Gaete (SHOA, Chili) Peter Foden et Jeff Pugh (NOC, Royaume-Uni) Begoña Pérez (Puertos del Estado, Espagne) Lesley Rickards (BODC, Royaume-Uni) Tilo Schöne (GFZ, Allemagne) Contributeurs au Supplément – Expériences pratiques Daryl Metters et John Ryan (Coastal Impacts Unit, Queensland, Australie) Christa von Hillebrandt-Andrade (NOAA, États-Unis), Rolf Vieten, Carolina Hincapié-Cárdenas et Sébastien Deroussi (IPGP, France) Juan Fierro et Jorge Gaete (SHOA, Chili) Gaël André, Noé Poffa, Guillaume Voineson, Vincent Donato, Séverine Enet (SHOM, France) et Laurent Testut (LEGOS, France) Stephan Mai et Ulrich Barjenbruch (BAFG, Allemagne) Elke Kühmstedt et Gunter Liebsch (BKG, Allemagne) Prakash Mehra, R.G. -
OCEANS ´09 IEEE Bremen
11-14 May Bremen Germany Final Program OCEANS ´09 IEEE Bremen Balancing technology with future needs May 11th – 14th 2009 in Bremen, Germany Contents Welcome from the General Chair 2 Welcome 3 Useful Adresses & Phone Numbers 4 Conference Information 6 Social Events 9 Tourism Information 10 Plenary Session 12 Tutorials 15 Technical Program 24 Student Poster Program 54 Exhibitor Booth List 57 Exhibitor Profiles 63 Exhibit Floor Plan 94 Congress Center Bremen 96 OCEANS ´09 IEEE Bremen 1 Welcome from the General Chair WELCOME FROM THE GENERAL CHAIR In the Earth system the ocean plays an important role through its intensive interactions with the atmosphere, cryo- sphere, lithosphere, and biosphere. Energy and material are continually exchanged at the interfaces between water and air, ice, rocks, and sediments. In addition to the physical and chemical processes, biological processes play a significant role. Vast areas of the ocean remain unexplored. Investigation of the surface ocean is carried out by satellites. All other observations and measurements have to be carried out in-situ using research vessels and spe- cial instruments. Ocean observation requires the use of special technologies such as remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), towed camera systems etc. Seismic methods provide the foundation for mapping the bottom topography and sedimentary structures. We cordially welcome you to the international OCEANS ’09 conference and exhibition, to the world’s leading conference and exhibition in ocean science, engineering, technology and management. OCEANS conferences have become one of the largest professional meetings and expositions devoted to ocean sciences, technology, policy, engineering and education.