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Barotropic Tide in the Northeast South China Sea
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Calhoun, Institutional Archive of the Naval Postgraduate School Calhoun: The NPS Institutional Archive Faculty and Researcher Publications Faculty and Researcher Publications 2004-10 Barotropic Tide in the Northeast South China Sea Beardsley, Robert C. Monterey, California. Naval Postgraduate School Vol.29, no.4, October 2004 http://hdl.handle.net/10945/35040 IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 29, NO. 4, OCTOBER 2004 1075 Barotropic Tide in the Northeast South China Sea Robert C. Beardsley, Timothy F. Duda, James F. Lynch, Senior Member, IEEE, James D. Irish, Steven R. Ramp, Ching-Sang Chiu, Tswen Yung Tang, Ying-Jang Yang, and Guohong Fang Abstract—A moored array deployed across the shelf break in data using satellite advanced very high-resolution radiometer, the northeast South China Sea during April–May 2001 collected altimeter, and other microwave sensors [8]. sufficient current and pressure data to allow estimation of the The SCS study area was centered over the shelf break near barotropic tidal currents and energy fluxes at five sites ranging in depth from 350 to 71 m. The tidal currents in this area were 21 55 N, 117 20 E, approximately 370 km west of the mixed, with the diurnal O1 and K1 currents dominant over the southern tip of Taiwan (Fig. 1). This area was chosen in part upper slope and the semidiurnal M2 current dominant over the for three reasons: 1) large-amplitude high-frequency internal shelf. The semidiurnal S2 current also increased onshelf (north- waves generated near the Luzon Strait propagate through the ward), but was always weaker than O1 and K1. -
Ocean Acoustic Tomography: a Missing Element of the Ocean Observing System
UACE2017 - 4th Underwater Acoustics Conference and Exhibition OCEAN ACOUSTIC TOMOGRAPHY: A MISSING ELEMENT OF THE OCEAN OBSERVING SYSTEM Brian Dushawa, John Colosib, Timothy Dudac, Matthew Dzieciuchd, Bruce Howee, Arata Kanekof, Hanne Sagena, Emmanuel Skarsoulisg, Xiaohua Zhuh aNansen Environmental and Remote Sensing Center, Thormøhlens gate 47, 5006 Bergen, NORWAY bNaval Postgraduate School, 833 Dyer Road, Monterey, CA 93943 USA cApplied Ocean Physics and Engineering, MS 11, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 USA dScripps Institution of Oceanography, University of California, San Diego 92093-0225 USA eOcean and Resources Engineering, University of Hawaii at Manoa, Honolulu HI 96822 USA fInstitute of Engineering, Hiroshima University, 1-3-2 Kagamiyama, Higashi-Hiroshima City, Hiroshima, JAPAN 739-8511 gFoundation for Research and Technology Hellas, Institute of Applied and Computational Mathematics, P.O. Box 1385, GR-71110 Heraklion, GREECE hSecond Institute of Oceanography, State Oceanic Administration, 36 Baochubei Road, Hangzhou, CHINA 310012 Brian Dushaw, Nansen Environmental and Remote Sensing Center, Thormøhlens gate 47, 5006 Bergen, NORWAY fax: (+47) 55 20 58 01, e-mail: [email protected] Abstract: Ocean acoustic tomography now has a long history with many observations and experiments that highlight the unique capabilities of this approach to detecting and understanding ocean variability. Examples include observations of deep mixing in the Greenland Sea, mode-1 internal tides radiating far into the ocean interior (coherent in time and space), relative vorticity on multiple scales, basin-wide and antipodal measures of temperature, barotropic currents, coastal processes in shallow water, and Arctic climate change. Despite the capabilities, tomography, and its simplified form thermometry, are not yet core observations within the Ocean Observing Systems (OOS). -
Observation of Rip Currents by Synthetic Aperture Radar
OBSERVATION OF RIP CURRENTS BY SYNTHETIC APERTURE RADAR José C.B. da Silva (1) , Francisco Sancho (2) and Luis Quaresma (3) (1) Institute of Oceanography & Dept. of Physics, University of Lisbon, 1749-016 Lisbon, Portugal (2) Laboratorio Nacional de Engenharia Civil, Av. do Brasil, 101 , 1700-066, Lisbon, Portugal (3) Instituto Hidrográfico, Rua das Trinas, 49, 1249-093 Lisboa , Portugal ABSTRACT Rip currents are near-shore cellular circulations that can be described as narrow, jet-like and seaward directed flows. These flows originate close to the shoreline and may be a result of alongshore variations in the surface wave field. The onshore mass transport produced by surface waves leads to a slight increase of the mean water surface level (set-up) toward the shoreline. When this set-up is spatially non-uniform alongshore (due, for example, to non-uniform wave breaking field), a pressure gradient is produced and rip currents are formed by converging alongshore flows with offshore flows concentrated in regions of low set-up and onshore flows in between. Observation of rip currents is important in coastal engineering studies because they can cause a seaward transport of beach sand and thus change beach morphology. Since rip currents are an efficient mechanism for exchange of near-shore and offshore water, they are important for across shore mixing of heat, nutrients, pollutants and biological species. So far however, studies of rip currents have mainly relied on numerical modelling and video camera observations. We show an ENVISAT ASAR observation in Precision Image mode of bright near-shore cell-like signatures on a dark background that are interpreted as surface signatures of rip currents. -
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 -
Lesson 8: Currents
Standards Addressed National Science Lesson 8: Currents Education Standards, Grades 9-12 Unifying concepts and Overview processes Physical science Lesson 8 presents the mechanisms that drive surface and deep ocean currents. The process of global ocean Ocean Literacy circulation is presented, emphasizing the importance of Principles this process for climate regulation. In the activity, students The Earth has one big play a game focused on the primary surface current names ocean with many and locations. features Lesson Objectives DCPS, High School Earth Science Students will: ES.4.8. Explain special 1. Define currents and thermohaline circulation properties of water (e.g., high specific and latent heats) and the influence of large bodies 2. Explain what factors drive deep ocean and surface of water and the water cycle currents on heat transport and therefore weather and 3. Identify the primary ocean currents climate ES.1.4. Recognize the use and limitations of models and Lesson Contents theories as scientific representations of reality ES.6.8 Explain the dynamics 1. Teaching Lesson 8 of oceanic currents, including a. Introduction upwelling, density, and deep b. Lecture Notes water currents, the local c. Additional Resources Labrador Current and the Gulf Stream, and their relationship to global 2. Extra Activity Questions circulation within the marine environment and climate 3. Student Handout 4. Mock Bowl Quiz 1 | P a g e Teaching Lesson 8 Lesson 8 Lesson Outline1 I. Introduction Ask students to describe how they think ocean currents work. They might define ocean currents or discuss the drivers of currents (wind and density gradients). Then, ask them to list all the reasons they can think of that currents might be important to humans and organisms that live in the ocean. -
Part III-2 Longshore Sediment Transport
Chapter 2 EM 1110-2-1100 LONGSHORE SEDIMENT TRANSPORT (Part III) 30 April 2002 Table of Contents Page III-2-1. Introduction ............................................................ III-2-1 a. Overview ............................................................. III-2-1 b. Scope of chapter ....................................................... III-2-1 III-2-2. Longshore Sediment Transport Processes ............................... III-2-1 a. Definitions ............................................................ III-2-1 b. Modes of sediment transport .............................................. III-2-3 c. Field identification of longshore sediment transport ........................... III-2-3 (1) Experimental measurement ............................................ III-2-3 (2) Qualitative indicators of longshore transport magnitude and direction ......................................................... III-2-5 (3) Quantitative indicators of longshore transport magnitude ..................... III-2-6 (4) Longshore sediment transport estimations in the United States ................. III-2-7 III-2-3. Predicting Potential Longshore Sediment Transport ...................... III-2-7 a. Energy flux method .................................................... III-2-10 (1) Historical background ............................................... III-2-10 (2) Description ........................................................ III-2-10 (3) Variation of K with median grain size................................... III-2-13 (4) Variation of K with -
Earth Science Ocean Currents May 12, 2020
High School Science Virtual Learning Earth Science Ocean Currents May 12, 2020 High School Earth Science Lesson: May 12, 2020 Objective/Learning Target: Students will understand major ocean currents and how they impact Earth. Let’s Get Started: 1. What is the difference between weather and climate? 2. What is an ocean? Let’s Get Started: Answer Key 1. Weather is local & short term, climate is regional and long term 2. The ocean is a huge body of saltwater that covers about 71 percent of the Earth's surface Lesson Activity: Directions: 1. Read through the Following slides. 2. Answer the questions on your own paper. MAJOR OCEAN CURRENTS Terms 1. Coriolis Effect movement of wind and water to the right or left that is caused by Earth’s rotation 2. upwelling vertical movement of water toward the ocean’s surface 3. surface current is an ocean current that moves water horizontally and does not reach a depth of more than 400m. 4. gyre is when major surface currents form a circular system. MAJOR OCEAN CURRENTS A current is a large volume of water flowing in a certain direction. CAUSES OF OCEAN CURRENTS 1. One cause of an ocean current is friction between wind and the ocean surface. ○ Earth’s prevailing winds influence the formation and direction of surface currents. ○ Ex: tides, waves 2. In addition to the wind, the direction surface currents flow depends on the Coriolis effect. ○ The Coriolis effect results from Earth’s rotation. It influences the direction of flow of Earth’s water and air. 3. -
Ocean Vocabulary
Mrs. Hansgen's 7th Grade Science Name Date Ocean Vocabulary wave period breaker El Nino neap tides Coriolis effect swelling whitecap tidal range trough high tide tsunami deep current crest spring tides low tide surf surface current storm surge wavelength upwelling Matching Match each definition with a word. 1. Lowest point of a wave 2. a white, foaming wave with a very steep crest that breaks in the open ocean before the wave gets close to the shore 3. A curving of a moving object from a straight path due to the Earth's rotation. 4. An ocean current formed when steady winds blow over the surface of the ocean. 5. rolling waves that move in a steady procession across the ocean 6. when the ocean tide reaches the highest point on the shoreline 7. An abnormal climate event that occurs every 2 to 7 years in the Pacific Ocean, causing changes in winds, currents, and weather patterns, that can lead to dramatic changes. 8. a wave that forms when a large volume of ocean water is suddenly moved up or down 9. The distance between two adjacent wave crests or wave troughs 10. tides with minimum daily tidal range that occur during the first and third quarters of the moon 11. Highest point of a wave 12. a process in which cold, nutrient-rich water from the deep ocean rises to the surface and replaces warm surface water 13. ocean tide at its lowest point on the shore 14. the area between the breaker zone and the shore 15. -
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. -
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. -
On Ocean Waveguide Acoustics
BOOKREVIEW ___________________________________________________ GEORGE V. FRISK ON OCEAN WAVEGUIDE ACOUSTICS acoustic waves with multilayered media is also an ac ACOUSTIC WAVEGUIDES: APPLICATIONS TO OCEANIC SCIENCE tive area of research in underwater acoustics. By C. Allen Boyles, Principal Professional Staff, In recent years, the inverse problem of determining The Johns Hopkins University Applied Physics Laboratory oceanographic properties from acoustic measurements Published by John Wiley & Son, New York, 1984. 321 pp. $46.95 has become increasingly important and has given rise to the term "acoustical oceanography," a variant of "ocean acoustics" that emphasizes the oceanograph ic implications of acoustic experiments. A major de The field of ocean acoustics is an active area of the velopment in this area is time-of-flight acoustic oretical and experimental research, with a continual tomography in which front and eddy intensity and ly expanding body of literature in research journals variability over hundreds of kilometers are measured and textbooks. Boyles' book is a welcome addition to acoustically. In ocean-bottom acoustics, direct inverse the literature and provides a useful text for both stu methods are being developed that utilize some mea dents and practitioners in the field. surement of the acoustic field, such as the plane wave Although electromagnetic waves are strongly ab reflection coefficient of the bottom, as direct input to sorbed by water, acoustic waves can, under the prop algorithms for determining the acoustic properties of er conditions, propagate over hundreds, even thou the bottom. This approach is to be contrasted with sands, of miles through the ocean. As a result, sound conventional techniques in which forward models for waves and sonar assume the major role in the ocean computing the acoustic field are run for different bot that electromagnetic waves and radar play in the at tom properties until best fits to the data are obtained. -
Assessment of Natural and Anthropogenic Sound Sources and Acoustic Propagation in the North Sea
UNCLASSIFIED Oude Waalsdorperweg 63 P.O. Box 96864 2509 JG The Hague The Netherlands TNO report www.tno.nl TNO-DV 2009 C085 T +31 70 374 00 00 F +31 70 328 09 61 [email protected] Assessment of natural and anthropogenic sound sources and acoustic propagation in the North Sea Date February 2009 Author(s) Dr. M.A. Ainslie, Dr. C.A.F. de Jong, Dr. H.S. Dol, Dr. G. Blacquière, Dr. C. Marasini Assignor The Netherlands Ministry of Transport, Public Works and Water Affairs; Directorate-General for Water Affairs Project number 032.16228 Classification report Unclassified Title Unclassified Abstract Unclassified Report text Unclassified Appendices Unclassified Number of pages 110 (incl. appendices) Number of appendices 1 All rights reserved. No part of this report may be reproduced and/or published in any form by print, photoprint, microfilm or any other means without the previous written permission from TNO. All information which is classified according to Dutch regulations shall be treated by the recipient in the same way as classified information of corresponding value in his own country. No part of this information will be disclosed to any third party. In case this report was drafted on instructions, the rights and obligations of contracting parties are subject to either the Standard Conditions for Research Instructions given to TNO, or the relevant agreement concluded between the contracting parties. Submitting the report for inspection to parties who have a direct interest is permitted. © 2009 TNO Summary Title : Assessment of natural and anthropogenic sound sources and acoustic propagation in the North Sea Author(s) : Dr.