Tide and Current Glossary
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Glossary Physics (I-Introduction)
1 Glossary Physics (I-introduction) - Efficiency: The percent of the work put into a machine that is converted into useful work output; = work done / energy used [-]. = eta In machines: The work output of any machine cannot exceed the work input (<=100%); in an ideal machine, where no energy is transformed into heat: work(input) = work(output), =100%. Energy: The property of a system that enables it to do work. Conservation o. E.: Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes. Equilibrium: The state of an object when not acted upon by a net force or net torque; an object in equilibrium may be at rest or moving at uniform velocity - not accelerating. Mechanical E.: The state of an object or system of objects for which any impressed forces cancels to zero and no acceleration occurs. Dynamic E.: Object is moving without experiencing acceleration. Static E.: Object is at rest.F Force: The influence that can cause an object to be accelerated or retarded; is always in the direction of the net force, hence a vector quantity; the four elementary forces are: Electromagnetic F.: Is an attraction or repulsion G, gravit. const.6.672E-11[Nm2/kg2] between electric charges: d, distance [m] 2 2 2 2 F = 1/(40) (q1q2/d ) [(CC/m )(Nm /C )] = [N] m,M, mass [kg] Gravitational F.: Is a mutual attraction between all masses: q, charge [As] [C] 2 2 2 2 F = GmM/d [Nm /kg kg 1/m ] = [N] 0, dielectric constant Strong F.: (nuclear force) Acts within the nuclei of atoms: 8.854E-12 [C2/Nm2] [F/m] 2 2 2 2 2 F = 1/(40) (e /d ) [(CC/m )(Nm /C )] = [N] , 3.14 [-] Weak F.: Manifests itself in special reactions among elementary e, 1.60210 E-19 [As] [C] particles, such as the reaction that occur in radioactive decay. -
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. -
The Mean Flow Field of the Tropical Atlantic Ocean
Deep-Sea Research II 46 (1999) 279—303 The mean flow field of the tropical Atlantic Ocean Lothar Stramma*, Friedrich Schott Institut fu( r Meereskunde, an der Universita( t Kiel, Du( sternbrooker Weg 20, 24105 Kiel, Germany Received 26 August 1997; received in revised form 31 July 1998 Abstract The mean horizontal flow field of the tropical Atlantic Ocean is described between 20°N and 20°S from observations and literature results for three layers of the upper ocean, Tropical Surface Water, Central Water, and Antarctic Intermediate Water. Compared to the subtropical gyres the tropical circulation shows several zonal current and countercurrent bands of smaller meridional and vertical extent. The wind-driven Ekman layer in the upper tens of meters of the ocean masks at some places the flow structure of the Tropical Surface Water layer as is the case for the Angola Gyre in the eastern tropical South Atlantic. Although there are regions with a strong seasonal cycle of the Tropical Surface Water circulation, such as the North Equatorial Countercurrent, large regions of the tropics do not show a significant seasonal cycle. In the Central Water layer below, the eastward North and South Equatorial undercurrents appear imbedded in the westward-flowing South Equatorial Current. The Antarcic Intermediate Water layer contains several zonal current bands south of 3°N, but only weak flow exists north of 3°N. The sparse available data suggest that the Equatorial Intermediate Current as well as the Southern and Northern Intermediate Countercurrents extend zonally across the entire equatorial basin. Due to the convergence of northern and southern water masses, the western tropical Atlantic north of the equator is an important site for the mixture of water masses, but more work is needed to better understand the role of the various zonal under- and countercur- rents in cross-equatorial water mass transfer. -
Fronts in the World Ocean's Large Marine Ecosystems. ICES CM 2007
- 1 - This paper can be freely cited without prior reference to the authors International Council ICES CM 2007/D:21 for the Exploration Theme Session D: Comparative Marine Ecosystem of the Sea (ICES) Structure and Function: Descriptors and Characteristics Fronts in the World Ocean’s Large Marine Ecosystems Igor M. Belkin and Peter C. Cornillon Abstract. Oceanic fronts shape marine ecosystems; therefore front mapping and characterization is one of the most important aspects of physical oceanography. Here we report on the first effort to map and describe all major fronts in the World Ocean’s Large Marine Ecosystems (LMEs). Apart from a geographical review, these fronts are classified according to their origin and physical mechanisms that maintain them. This first-ever zero-order pattern of the LME fronts is based on a unique global frontal data base assembled at the University of Rhode Island. Thermal fronts were automatically derived from 12 years (1985-1996) of twice-daily satellite 9-km resolution global AVHRR SST fields with the Cayula-Cornillon front detection algorithm. These frontal maps serve as guidance in using hydrographic data to explore subsurface thermohaline fronts, whose surface thermal signatures have been mapped from space. Our most recent study of chlorophyll fronts in the Northwest Atlantic from high-resolution 1-km data (Belkin and O’Reilly, 2007) revealed a close spatial association between chlorophyll fronts and SST fronts, suggesting causative links between these two types of fronts. Keywords: Fronts; Large Marine Ecosystems; World Ocean; sea surface temperature. Igor M. Belkin: Graduate School of Oceanography, University of Rhode Island, 215 South Ferry Road, Narragansett, Rhode Island 02882, USA [tel.: +1 401 874 6533, fax: +1 874 6728, email: [email protected]]. -
Multidecadal and NA0 Related Variability in a Numerical Model of the North Atlantic Circulation
Multidecadal and NA0 related variability in a numerical model of the North Atlantic circulation Multidekadische und NA0 bezogene Variabilitäin einem numerischen Modell des Nordatlantiks Jennifer P. Brauch Ber. Polarforsch. Meeresforsch. 478 (2004) ISSN 1618 - 3193 Jennifer P. Brauch UVic Climate Modelling Research Group PO Box 3055, Victoria, BC, V8W 3P6, Canada http://climate.uvic.ca/ [email protected] Die vorliegende Arbeit ist die inhaltlich unverändert Fassung einer Dis- sertation, die 2003 im Fachbereich Physik/Elektrotechnik der Universitä Bremen vorgelegt wurde. Sie ist in elektronischer Form erhältlic unter http://elib.suub.uni-brernen.de/. Contents Zusammenfassung iii Abstract V 1 Introduction 1 2 Background 5 2.1 Main Characteristics of the Arctic and North Atlantic Ocean .... 5 2.1.1 Bathymetry ............................ 5 2.1.2 Major currents .......................... 7 2.1.3 Hydrography ........................... 8 2.1.4 Seaice ............................... 11 2.1.5 Convection ............................ 12 2.2 Variability ................................. 13 2.2.1 NA0 ................................ 13 2.2.2 Variability in the Arctic Mediterranean ............ 17 2.2.3 GSA ................................19 2.2.4 Oscillations in ocean models .................. 20 3 Model description 3.1 Ocean model ................................ 3.1.1 Equations ............................. 3.1.2 Setup ................................ 3.2 Sea Ice model ............................... 3.2.1 Equations ............................ -
Hunting Hours Time Zone A
WHEN AND WHERE TO HUNT WHEN AND WHERE Hunting Hours Time Zone A. Hunting Hours for Bear, Deer, Fall Wild Turkey, Furbearers, Shown is a map of the hunting-hour time zones. Actual legal hunting hours for and Small Game bear, deer, fall wild turkey, furbearer, and small game for Time Zone A are shown One-half hour before sunrise to one-half hour after sunset (adjusted for in the table at right. Hunting hours for migratory game birds are different and are daylight saving time). For hunt dates not listed in the table, please consult your published in the current-year Waterfowl Digest. local newspaper. 2016 Sept. Oct. Nov. Dec. To determine the opening (a.m.) and closing (p.m.) time for any day in another Note: time zone, add the minutes shown below to the times listed in the Time Zone A • Woodcock and teal Date AM PM AM PM AM PM AM PM Hunting Hours Table. hunting hours are 1 6:28 8:35 7:00 7:43 7:36 6:55 7:12 5:31 The hunting hours listed in the table reflect Eastern Standard Time, with an sunrise to sunset. 2 6:29 8:34 7:01 7:41 7:38 6:54 7:14 5:30 adjustment for daylight saving time. If you are hunting in Gogebic, Iron, Dickinson, • Spring turkey hunting 3 6:30 8:32 7:02 7:39 7:39 6:52 7:15 5:30 or Menominee counties (Central Standard Time), you must make an additional hours are one-half 4 6:31 8:30 7:03 7:38 7:40 6:51 7:16 5:30 adjustment to the printed time by subtracting one hour. -
Daylight Saving Time (DST)
Daylight Saving Time (DST) Updated September 30, 2020 Congressional Research Service https://crsreports.congress.gov R45208 Daylight Saving Time (DST) Summary Daylight Saving Time (DST) is a period of the year between spring and fall when clocks in most parts of the United States are set one hour ahead of standard time. DST begins on the second Sunday in March and ends on the first Sunday in November. The beginning and ending dates are set in statute. Congressional interest in the potential benefits and costs of DST has resulted in changes to DST observance since it was first adopted in the United States in 1918. The United States established standard time zones and DST through the Calder Act, also known as the Standard Time Act of 1918. The issue of consistency in time observance was further clarified by the Uniform Time Act of 1966. These laws as amended allow a state to exempt itself—or parts of the state that lie within a different time zone—from DST observance. These laws as amended also authorize the Department of Transportation (DOT) to regulate standard time zone boundaries and DST. The time period for DST was changed most recently in the Energy Policy Act of 2005 (EPACT 2005; P.L. 109-58). Congress has required several agencies to study the effects of changes in DST observance. In 1974, DOT reported that the potential benefits to energy conservation, traffic safety, and reductions in violent crime were minimal. In 2008, the Department of Energy assessed the effects to national energy consumption of extending DST as changed in EPACT 2005 and found a reduction in total primary energy consumption of 0.02%. -
Mapping Current and Future Priorities
Mapping Current and Future Priorities for Coral Restoration and Adaptation Programs International Coral Reef Initiative (ICRI) Ad Hoc Committee on Reef Restoration 2019 Interim Report This report was prepared by James Cook University, funded by the Australian Institute for Marine Science on behalf of the ICRI Secretariat nations Australia, Indonesia and Monaco. Suggested Citation: McLeod IM, Newlands M, Hein M, Boström-Einarsson L, Banaszak A, Grimsditch G, Mohammed A, Mead D, Pioch S, Thornton H, Shaver E, Souter D, Staub F. (2019). Mapping Current and Future Priorities for Coral Restoration and Adaptation Programs: International Coral Reef Initiative Ad Hoc Committee on Reef Restoration 2019 Interim Report. 44 pages. Available at icriforum.org Acknowledgements The ICRI ad hoc committee on reef restoration are thanked and acknowledged for their support and collaboration throughout the process as are The International Coral Reef Initiative (ICRI) Secretariat, Australian Institute of Marine Science (AIMS) and TropWATER, James Cook University. The committee held monthly meetings in the second half of 2019 to review the draft methodology for the analysis and subsequently to review the drafts of the report summarising the results. Professor Karen Hussey and several members of the ad hoc committee provided expert peer review. Research support was provided by Melusine Martin and Alysha Wincen. Advisory Committee (ICRI Ad hoc committee on reef restoration) Ahmed Mohamed (UN Environment), Anastazia Banaszak (International Coral Reef Society), -
Study of Earth's Gravity Tide and Ocean Loading
CHINESE JOURNAL OF GEOPHYSICS Vol.49, No.3, 2006, pp: 657∼670 STUDY OF EARTH’S GRAVITY TIDE AND OCEAN LOADING CHARACTERISTICS IN HONGKONG AREA SUN He-Ping1 HSU House1 CHEN Wu2 CHEN Xiao-Dong1 ZHOU Jiang-Cun1 LIU Ming1 GAO Shan2 1 Key Laboratory of Dynamical Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2 Department of Land Surveying and Geoinformatics, Hong-Kong Polytechnic University, Hung Hom, Knowloon, Hong Kong Abstract The tidal gravity observation achievements obtained in Hongkong area are introduced, the first complete tidal gravity experimental model in this area is obtained. The ocean loading characteristics are studied systematically by using global and local ocean models as well as tidal gauge data, the suitability of global ocean models is also studied. The numerical results show that the ocean models in diurnal band are more stable than those in semidiurnal band, and the correction of the change in tidal height plays a significant role in determining accurately the phase lag of the tidal gravity. The gravity observation residuals and station background noise level are also investigated. The study fills the empty of the tidal gravity observation in Crustal Movement Observation Network of China and can provide the effective reference and service to ground surface and space geodesy. Key words Hongkong area, Tidal gravity, Experimental model, Ocean loading 1 INTRODUCTION The Earth’s gravity is a science studying the temporal and spatial distribution of the gravity field and its physical mechanism. Generally, its achievements can be used in many important domains such as space science, geophysics, geodesy, oceanography, and so on. -
Assessment of DUACS Sentinel-3A Altimetry Data in the Coastal Band of the European Seas: Comparison with Tide Gauge Measurements
remote sensing Article Assessment of DUACS Sentinel-3A Altimetry Data in the Coastal Band of the European Seas: Comparison with Tide Gauge Measurements Antonio Sánchez-Román 1,* , Ananda Pascual 1, Marie-Isabelle Pujol 2, Guillaume Taburet 2, Marta Marcos 1,3 and Yannice Faugère 2 1 Instituto Mediterráneo de Estudios Avanzados, C/Miquel Marquès, 21, 07190 Esporles, Spain; [email protected] (A.P.); [email protected] (M.M.) 2 Collecte Localisation Satellites, Parc Technologique du Canal, 8-10 rue Hermès, 31520 Ramonville-Saint-Agne, France; [email protected] (M.-I.P.); [email protected] (G.T.); [email protected] (Y.F.) 3 Departament de Física, Universitat de les Illes Balears, Cra. de Valldemossa, km 7.5, 07122 Palma, Spain * Correspondence: [email protected]; Tel.: +34-971-61-0906 Received: 26 October 2020; Accepted: 1 December 2020; Published: 4 December 2020 Abstract: The quality of the Data Unification and Altimeter Combination System (DUACS) Sentinel-3A altimeter data in the coastal area of the European seas is investigated through a comparison with in situ tide gauge measurements. The comparison was also conducted using altimetry data from Jason-3 for inter-comparison purposes. We found that Sentinel-3A improved the root mean square differences (RMSD) by 13% with respect to the Jason-3 mission. In addition, the variance in the differences between the two datasets was reduced by 25%. To explain the improved capture of Sea Level Anomaly by Sentinel-3A in the coastal band, the impact of the measurement noise on the synthetic aperture radar altimeter, the distance to the coast, and Long Wave Error correction applied on altimetry data were checked. -
Surface Currents Near the Greater and Lesser Antilles
SURFACE CURRENTS NEAR THE GREATER AND LESSER ANTILLES by C.P. DUNCAN rl, S.G. SCHLADOW1'1 and W.G. WILLIAMS SUMMARY The surface flow around the Greater and Lesser Antilles is shown to differ considerably from the widely accepted current system composed of the Caribbean Current and Antilles Current. The most prominent features deduced from dynamic topography are a flow from the north into the Caribbean near Puerto Rico and a permanent eastward-flowing counter-current in the Caribbean itself between Puerto Rico and Venezuela. Noticeably absent is the Antilles Current. A satellite-tracked buoy substantiates the slow southward flow into the Caribbean and the absence of the Antilles Current. INTRODUCTION Pilot Charts for the North Atlantic and the Caribbean Sea (Defense Mapping Agency, 1968) show westerly surface currents to the North and South of Puerto Rico. The Caribbean Current is presented as an uninterrupted flow which passes through the Caribbean Sea, Yucatan Straits, Gulf of Mexico, and Florida Straits to become the Gulf Stream. It is joined off the east coast of Florida by the Antilles Current which is shown as flowing westwards along the north coast of Puerto Rico and then north-westerly along the northern edge of the Bahamas (BOISVERT, 1967). These surface currents are depicted as extensions of the North Equatorial Current and the Guyana Current, and as forming part of the subtropical gyre. As might be expected in the absence of a western boundary, the flow is slow-moving, shallow and broad. This interpretation of the surface currents is also presented by WUST (1964) who employs the same set of ship’s drift observations as are used in the Pilot Charts. -
The Impact of Sea-Level Rise on Tidal Characteristics Around Australia
The impact of sea-level rise on tidal characteristics around Australia ANGOR UNIVERSITY Harker, Alexander; Green, Mattias; Schindelegger, Michael; Wilmes, Sophie- Berenice Ocean Science DOI: 10.5194/os-2018-104 PRIFYSGOL BANGOR / B Published: 19/02/2019 Publisher's PDF, also known as Version of record Cyswllt i'r cyhoeddiad / Link to publication Dyfyniad o'r fersiwn a gyhoeddwyd / Citation for published version (APA): Harker, A., Green, M., Schindelegger, M., & Wilmes, S-B. (2019). The impact of sea-level rise on tidal characteristics around Australia. Ocean Science, 15(1), 147-159. https://doi.org/10.5194/os- 2018-104 Hawliau Cyffredinol / General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. 07. Oct. 2021 Ocean Sci., 15, 147–159, 2019 https://doi.org/10.5194/os-15-147-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License.