DOCSLIB.ORG

Great Ocean Conveyor

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Great Ocean Conveyor RESEARCH If you Google the phrase “Great waters,” says Susan Lozier, professor the dominant pathway for Labrador Ocean Conveyor,” one of the first of physical oceanography and chair Sea water,” Lozier says. “This shows images that will likely pop up on your of the Division of Earth and Ocean that the concept of the deep flow computer screen is a map of the North Sciences at the Nicholas School. operating like a conveyor belt doesn’t study Atlantic Ocean with “If this hypothesis were true,” she hold anymore. The pathways are more Uncharted Interior Ocean Pathways color-coded arrows explains, “it would significantly diffuse. They spread out much farther showing a loop- affect how scientists measure into the eddy-filled deep ocean, so it’s Using an Armada of Specially ing, conveyor climate signals in the deep going to be more difficult for scientists Designed Floats, Scientists Get a belt-like path ocean. But the hitch was, to measure climate change signals.” that deep we lacked the direct Lozier and Bower first conceived of New Look at the ‘Great Ocean ocean cur- evidence to prove it.” their ambitious project eight years ago, Conveyor’ with Major Implications for rents follow Now, a major study in response to earlier studies, including as they flow led by Lozier and long- a widely cited paper Lozier published Global Climate Change Research north from time research collaborator in Science in 1997 that strongly the equator Amy Bower, a senior suggested unknown interior pathways and south from scientist in the Department played an important role in deep by Tim Lucas the polar seas. of Physical Oceanography circulation of the North Atlantic. A It’s a model at Woods Hole Oceanographic study of floats in the Labrador Sea in that’s been used for Institution (WHOI), has provided the late 1990s by scientists at the more than 20 years to explain that critical evidence. Scripps Institute of Oceanography how the oceans distribute heat and The study, published in the May 14 and Woods Hole seemingly confirmed influence our climate, and—more issue of the journal Nature, used Lozier’s hypothesis, but results recently—to shape scientists’ hypotheses data from computer models from this study were not about the amount and fate of carbon and an armada of sophisti- convincing, in part because dioxide that oceans sequester from cated Range and Fixing the submersible floats our atmosphere. of Sound (RAFOS) used to collect the data In the conveyor belt paradigm, floats, deployed during had to return repeatedly currents warmed by the Gulf Stream research cruises in the to the surface to report move northward and release their heat North Atlantic over the their positions and into the atmosphere, leaving the waters course of three years, to observations to satellite themselves colder and denser. At their show that most of the receivers. This meant the northern terminus, the dense, cold southward flow of cold floats’ data could have been waters sink beneath the polar seas and water from the Labrador Sea biased by upper ocean currents flow back southward along a discrete, moved not along the Deep Western during the floats periodic ascents. well-defined path called the Deep Boundary Current, but instead “The challenge for Amy and me,” Western Boundary Current that hugs followed previously uncharted Lozier recalls, “was finding a way to the continental shelf between Canada “interior pathways” in the collect direct evidence, free of possible and the equator. To replace this deep ocean. Groups of bias, that would test our hypothesis sinking water, warm surface six RAFOS floats were and either prove or disprove it.” waters from the tropics are released into the With funding from the National pulled northward again, Labrador Sea every Science Foundation and technical creating a continuous loop three months from support from the staff at Woods Hole, of climate-moderating 2003 through 2005 Lozier and Bower devised an elaborate currents. and were left in the plan they hoped would surmount that It’s a nice, neat, tidy water to collect data challenge. system. for two years. Bower and her colleagues built Oceanographers, however, Only 8 percent of 76 specially designed RAFOS floats have long known that this para- the floats followed the configured to submerge to a depth of digm for describing deep ocean circula- conveyor belt of the Deep Western 700 to 1,500 meters below the ocean’s tion is an oversimplification—a useful Boundary Current, Lozier and Bower’s surface—within the layer of water enough depiction of the general principle, study found. About 75 percent of them where a major portion of the cold, but missing key pieces of the puzzle. escaped that pathway and drifted into south-flowing current of Labrador Sea “We’ve hypothesized, based on the open ocean before reaching the water flows. studies using indirect evidence like Grand Banks. A RAFOS float weighs about 22 ocean salinities and temperatures, that “Eight percent is a remarkably low pounds (10 kilograms) and can be there are re-circulations, which cause number in light of expectations that dropped over the side of a small boat alternative pathways for these deep the Deep Western Boundary Current is by one person, although they are most dukenvironment 18 DEANS P commonly deployed from large Lozier, Gary and Böning traced their released since the Industrial Revolution AGE oceanographic research vessels. The pathways and found that the spread of is stored in the ocean,” says Lozier. float’s electronics are housed in a thin, the e-floats was “very similar” to that “The question is, how much is stored With the Dean for six-and-a-half foot (two meter) glass of the actual RAFOS float trajectories at depth? And for how long? tube that vaguely resembles a giant after two years. “To answer these questions, we glass thermometer or overhead fluores- The combined observations from need to learn more about where these um cent strip light. the real and simulated experi- deep, cold currents flow, how they act Once deployed, the floats ments provided clear evidence as sinks for heat and carbon dioxide, drifted underwater with that southward interior and their ultimate fate in the ocean,” the currents for two years, pathways in the deep ocean she explains. recording location are more important than Toward this end, Bower and Lozier information as well as previously shown for the plan to expand their research in temperature and pressure transport of Labrador Sea coming years to study the southward measurements once a day. water to the subtropics, says flow of cold water originating even After two years, they returned Peter B. Rhines, professor of farther north in the remote waters of to the surface and transmitted their oceanography and atmospheric the Greenland Sea. Can They Stop the Impending Train Wreck? by William L. Chameides treasure trove of stored data to sciences at the University of Washington. Additionally, Lozier hopes to make scientists back in the lab through “Drs. Bower and Lozier have brought use of a new generation of high-tech The fall approaches; a new academic year begins and with of natural habitat to agricultural land at the expense of the the ARGOS satellite-based data the remarkable technology of neutrally underwater submersibles to speed and it a new class of bright and talented students arrived at the genetic treasures of a biodiverse world. retrieval system. buoyant deep, drifting buoys to bear on smooth the data-collection process. Nicholas School. This year’s class is especially noteworthy, not A reasonable response, indeed the only response to the To communicate with the floats a matter of great importance to global In the past five years, she explains, only for its stellar qualifications and size—one of the best and problem of depleting resources, is to adopt a more sustainable and to track their positions while they climate. The global ocean circulation researchers have developed program- largest we have ever seen—but also because this is the first approach: use less, conserve more, be more efficient, recycle. were still submerged, the researchers which ventilates the great depths of the mable, unmanned battery-operated class entering Nicholas since the great economic meltdown Converting our current unsustainable practices to more deployed anchored low-amplitude seas is often portrayed as a ‘conveyor units that can glide through the deep of 2008-09. sustainable ones would be hard enough under normal circum- sound beacons in the general area of belt.’ While this is a useful analogy, ocean, collect real-time data at pre-set Despite the sobering events of the past year, this year’s stances. But these are hardly normal circumstances. Today the experiment. The beacons were set their work establishes conclusively that depths and then surface and transmit group seems as idealistic and energetic as any. They are ready planet Earth is populated by some 6.8 billion people; a little less to “ping” automatically every day, ocean eddies—swirling water masses, the data back to scientists in the lab to roll up their sleeves and make the world a better place, and than half of these live on less than $2.50 per day according enabling the scientists to determine much like the rotating storms of the via satellite, avoiding the long time perhaps more so than in previous years, confident that they will the World Bank. Sometime near the middle of this century, the distance between the floats and atmosphere—stir the deep ocean. delays associated with RAFOS floats help make the world a better place. Perhaps having witnessed demographers tell us, there will be about 9 billion of us—give beacons, based on the time delay In doing so, the eddies spread the or the potential data bias of the and survived the meltdown, they feel empowered.
Load more

Recommended publications
  • Ebb and Flow Tides and Life on Our Once and Future Planet
    This article has This been published in or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval portionthe ofwith any permitted articleonly photocopy by is machine, of this reposting, means or collective or other redistirbution BOOK REVIEWS Ebb and Flow Oceanography Tides and Life on Our Once and Future Planet , V By Tom Koppel, The Dundurn Group, which is the loss of much of the fleet of olume 21, Number 2, a quarterly journal of journal The olume 21, Number 2, a quarterly 2007, 296 pages, ISBN 9781550027266, Alexander the Great due to a tidal bore), Paperback, $26.99 US coastal ecosystems, modern analysis, and extracting energy from tides. Chapter 1 REVIEWED BY JOHN L. LuiCK contains an account of the ancient tidal dockyards at Lothal, India—surely a can- Ebb and Flow: Tides and Life on Our didate for “Engineering Wonders of the Once and Future Planet is well titled. It Ancient World.” The most ambitious and O tells the story of tides, why they matter, original chapter is the final one, whose ceanography Society. Society. ceanography what causes them, and how they have three subheadings are Sea Level Change changed over time. The author, Tom Causes Intertidal Zones to Migrate; Giant all sorts of ammonia and phosphoric Koppel, is not an analyst or theoretician Ancient Tides and Earth’s Rotation; and salts.” Again, tides are shown to play a C of tides but a man of inquisitive mind The Origin, Evolution, and Future of Life crucial role in both the origin and the opyright 2008 by The 2008 by opyright and substantial beachcombing and on Earth.
    [Show full text]
  • The Evolution and Demise of North Brazil Current Rings*
    VOLUME 36 JOURNAL OF PHYSICAL OCEANOGRAPHY JULY 2006 The Evolution and Demise of North Brazil Current Rings* DAVID M. FRATANTONI Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts PHILIP L. RICHARDSON Department of Physical Oceanography, Woods Hole Oceeanographic Institution, and Associated Scientists at Woods Hole, Woods Hole, Massachusetts (Manuscript received 27 May 2004, in final form 26 October 2005) ABSTRACT Subsurface float and surface drifter observations illustrate the structure, evolution, and eventual demise of 10 North Brazil Current (NBC) rings as they approached and collided with the Lesser Antilles in the western tropical Atlantic Ocean. Upon encountering the shoaling topography east of the Lesser Antilles, most of the rings were deflected abruptly northward and several were observed to completely engulf the island of Barbados. The near-surface and subthermocline layers of two rings were observed to cleave or separate upon encountering shoaling bathymetry between Tobago and Barbados, with the resulting por- tions each retaining an independent and coherent ringlike vortical circulation. Surface drifters and shallow (250 m) subsurface floats that looped within NBC rings were more likely to enter the Caribbean through the passages of the Lesser Antilles than were deeper (500 or 900 m) floats, indicating that the regional bathymetry preferentially inhibits transport of intermediate-depth ring components. No evidence was found for the wholesale passage of rings through the island chain. 1. Introduction ration from the NBC, anticyclonic rings with azimuthal speeds approaching 100 cm sϪ1 move northwestward a. Background toward the Caribbean Sea on a course parallel to the The North Brazil Current (NBC) is an intense west- South American coastline (Johns et al.
    [Show full text]
  • Lagrangian Measurement of Subsurface Poleward Flow Between 38 Degrees N and 43 Degrees N Along the West Coast of the United States During Summer, 1993
    CORE Metadata, citation and similar papers at core.ac.uk Provided by Calhoun, Institutional Archive of the Naval Postgraduate School Calhoun: The NPS Institutional Archive Faculty and Researcher Publications Faculty and Researcher Publications 1996-09-01 Lagrangian Measurement of subsurface poleward Flow between 38 degrees N and 43 degrees N along the West Coast of the United States during Summer, 1993 Collins, Curtis A. Geophysical Research Letters, Vol. 23, No. 18, pp. 2461-2464, September 1, 1996 http://hdl.handle.net/10945/45730 GEOPHYSICAL RESEARCH LETTERS, VOL. 23, NO. 18, PAGES 2461-2464, SEPTEMBER 1, 1996 Lagrangian Measurement of subsurface poleward Flow between 38øN and 43øN along the West Coast of the United States during Summer, 1993 CurtisA. Collins,Newell Garfield, Robert G. Paquette,and Everett Carter 1 Departmentof Oceanography,Naval Postgraduate School, Monterey, California Abstract. SubsurfaceLagrangian measurementsat about Undercurrentalong the coastsof California and Oregon. We 140 m showedthat the pathof the CaliforniaUndercurrent lay are using quasi-isobaric(float depth controlled primarily by next to the continentalslope betweenSan Francisco(37.80N) the pressureeffect on density)RAFOS floats (Rossby et al., and St. GeorgeReef (41.8øN) duringmid-summer 1993. The 1986) to make these measurements. A RAFOS float consists meanspeed along this 500 km pathwas 8 cms-1. Theflow at of a hydrophonemounted in a glasstube that is about2 meters this depth was not disturbedby upwelling centersat Point long. These hydrophonesreceive signals from three sound Reyesor CapeMendocino. Restfits also demonstratethe abil- sources that were moored 400 km offshore between 34.3øN and ity to acousticallytrack floats located well above the sound 40.4øN.The sound sources emit 15 W, 80 s signalsa•t 260 Hz channelaxis along the California coast.
    [Show full text]
  • Particle Pathways in the Gulf Stream
    Particle Pathways and P-T Shaw2 in the Gulf Stream Abstract East of Cape Hatteras, the Gulf Stream front separates two water masses: Sargasso Sea water to the south and the An experiment is under way to study the kinematics, dynamics, and cold slope waters to its north. The sharpness of the water mass path evolution of the Gulf Stream front between Cape Hatteras and boundary along the current's cyclonic edge and its coincidence 60°W. The Rafos float, which can track the true motion of water with the stream suggests that the front is impermeable to parcels along density surfaces which slope steeply across the Gulf Stream, has recently been developed for this study. These instruments cross-stream exchange of water. (It should be noted that this are launched in the center of the Gulf Stream every 5-15 days for a distinction of separate water masses loses validity below the 30-day mission. Each float provides a trajectory and a continuous midthermocline, where increasing uniformity of water prop- record of temperature and pressure along the trajectory. Our results erties suggests greater cross-stream exchange.) The Gulf so far show that: a) cross-stream motion has a significant vertical -1 Stream is not so isolated from the Sargasso Sea, however. Be- component (ranging to some 0.1 cm • s ) compared to vertical veloc- ities in midocean; b) floats systematically shoal (upwell) as they ap- tween the Florida Straits and Cape Hatteras the transport of proach anticyclonic meanders and deepen (downwell) as they ap- water more than doubles, with nearly all the new water coming proach cyclonic meanders; c) more than half of the floats launched from the Sargasso Sea.
    [Show full text]
  • Characteristics of Intermediate Water Flow in the Benguela Current As
    Deep-Sea Research II 50 (2003) 87–118 Characteristics of intermediate water flow in the Benguela current as measured with RAFOS floats P.L. Richardsona,*, S.L. Garzolib a Department of Physical Oceanography, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543, 3 Water Street, P.O. Box 721, USA b Atlantic Oceanographic and Meteorological Laboratory, NOAA, 4301 Rickenbacker Causeway, Miami, FL 33149, USA Received 28 September 2001; accepted 26 July 2002 Abstract Seven floats (not launched in rings) crossed over the mid-Atlantic Ridge in the Benguela extension with a mean westward velocity of around 2 cm=s between 22S and 35S. Two Agulhas rings crossed over the mid-Atlantic Ridge with a mean velocity of 5:7cm=s toward 2851: This implies they translated at around 3:8cm=s through the background velocity field near 750 m: The boundaries of the Benguela Current extension were clearly defined from the observations. At 750 m the Benguela extension was bounded on the south by 35S and the north by an eastward current located between 18S and 21S. Other recent float measurements suggest that this eastward current originates near the Trindade Ridge close to the western boundary and extends across most of the South Atlantic, limiting the Benguela extension from flowing north of around 20S. The westward transport of the Benguela extension was estimated to be 15 Sv by integrating the mean westward velocities from 22S to 35S and multiplying by the 500 m estimated thickness of intermediate water. Roughly 1.5 Sv of this are transported by the B3 Agulhas rings that cross the mid-Atlantic Ridge each year (as observed with altimetry).
    [Show full text]
  • Spatial and Interannual Variability in Mesoscale Circulation in the Northern California Current System Julie E
    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113, C04015, doi:10.1029/2007JC004256, 2008 Click Here for Full Article Spatial and interannual variability in mesoscale circulation in the northern California Current System Julie E. Keister1 and P. Ted Strub1 Received 31 March 2007; revised 16 October 2007; accepted 5 December 2007; published 12 April 2008. [1] We used wavelet analyses of sea surface height (SSH) from >13 years of satellite altimeter data to characterize the variability in mesoscale circulation in the northern California Current (35°N–49°N) and explore the mechanisms of variability. We defined ‘‘mesoscale’’ circulation as features, such as eddies and filaments, which have 50- to 300-km length scales and 4- to 18-week temporal scales. Fluctuations in SSH caused by such features were reflected in wavelet analyses as power (energy). Spatial and interannual variation in mesoscale energy was high. Energy was highest at 38°N, decreasing to the north and south. Between 43°N and 48°N, energy was low. Zonally, mesoscale energy was highest between 125°W and 129°W at latitudes south of 44°N; very little power occurred in the deep ocean west of 130°W. Energy peaked during summer/fall in most years. The primary climate signals were suppressed energy during La Nin˜a and cold years and increased energy during El Nin˜o events. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling mesoscale circulation. We hypothesize that climate affects mesoscale energy through changes in both potential and kinetic energy in the form of density gradients and coastal upwelling winds.
    [Show full text]
  • Deep Eddies in the Gulf of Mexico Observed with Floats
    NOVEMBER 2018 F U R E Y E T A L . 2703 Deep Eddies in the Gulf of Mexico Observed with Floats HEATHER FUREY AND AMY BOWER Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts PAULA PEREZ-BRUNIUS Department of Physical Oceanography, Ensenada Center for Scientific Research and Higher Education (CISESE), Ensenada, Mexico PETER HAMILTON North Carolina State University, Raleigh, North Carolina ROBERT LEBEN Colorado Center for Astrodynamics Research, University of Colorado Boulder, Boulder, Colorado (Manuscript received 20 November 2017, in final form 9 August 2018) ABSTRACT A new set of deep float trajectory data collected in the Gulf of Mexico from 2011 to 2015 at 1500- and 2500-m depths is analyzed to describe mesoscale processes, with particular attention paid to the western Gulf. Wavelet analysis is used to identify coherent eddies in the float trajectories, leading to a census of the basinwide coherent eddy population and statistics of the eddies’ kinematic properties. The eddy census reveals a new formation region for anticyclones off the Campeche Escarpment, located northwest of the Yucatan Peninsula. These eddies appear to form locally, with no apparent direct connection to the upper layer. Once formed, the eddies drift westward along the northern edge of the Sigsbee Abyssal Gyre, located in the southwestern Gulf of Mexico over the abyssal plain. The formation mechanism and upstream sources for the Campeche Escarpment eddies are explored: the observational data suggest that eddy formation may be linked to the collision of a Loop Current eddy with the western boundary of the Gulf. Specifically, the disintegration of a deep dipole traveling under the Loop Current eddy Kraken, caused by the interaction with the northwestern continental slope, may lead to the acceleration of the abyssal gyre and the boundary current in the Bay of Campeche region.
    [Show full text]
  • High Frequency Subsurface Lagrangian Measurements in the California Current with RAFOS Floats
    Calhoun: The NPS Institutional Archive Theses and Dissertations Thesis Collection 1995-09 High frequency subsurface Lagrangian measurements in the California Current with RAFOS floats Benson, Kirk R. Monterey, California. Naval Postgraduate School http://hdl.handle.net/10945/35108 NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS HIGH FREQUENCY SUBSURFACE LAGRANGIAN MEASUREMENTS IN THE CALIFORNIA CURRENT WITH RAFOS FLOATS by Kirk R. Benson September, 1995 Thesis Advisor: Newell Garfield Second Reader: Robert G. Paquette Approved for public release; distribution is unlimited. 19960402 122 DTic qoMjf&Y mürmam l DISCLAIMS! NOTICE THIS DOCUMENT IS BEST QUALITY AVAILABLE. THE COPY FURNISHED TO DTIC CONTAINED A SIGNIFICANT NUMBER OF PAGES WHICH DO NOT REPRODUCE LEGIBLY. REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704- Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or an} other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188) Washington DC 20503. ___^__ 1. AGENCY USE ONLY (Leave REPORT DATE 3.REPORT TYPE AND DATES blank) September 1995 COVERED Master's Thesis 4. TITLE AND SUBTITLE High Frequency Subsurface Lagrangian FUNDING NUMBERS Measurements in the California Current with RAFOS Floats 6. AUTHOR(S) Kirk R. Benson 7.
    [Show full text]
  • Feasibility of Disposal of High-Level Radioactive Waste Into the Seabed
    FEASIBILITY OF DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTE INTO THE SEABED VOLUME5 DISPERSAL OF RADIONUCLIDES IN THE OCEANS : MODELS, DATA SETS AND REGIONAL DESCRIPTIONS IT 11.0. MABŒTTA AMD mfSDOIOlB NUCLEAR ENERGY AGENCY ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT ORDER FORM SPECIAL 30 % DISCOUNT Use this order form to receive a 30 % discount when you purchase the entire set of the 8 volume series "Feasibility of Disposal of High-Level Radioactive Waste into the Seabed", published by the OECD Nuclear Energy Agency. Please enter my order for ....set(s) at the special 30 % discounted price of FF994 £116.00 US$219 DM427 The volumes may also be purchased individually copy(ies) Volume 1 - OVERVIEW OF RESEARCH AND CONCLUSIONS (66 88 09 1) ISBN 92-64-13164-7 FF90 US$20.00 111.00 DM39 copy(ies) Volume 2 - RADIOLOGICAL ASSESSMENT (66 88 10 1) ISBN 92-64-13165-5 FF220 US$48.50 tn .00 DM95 copy(ies) Volume 3 - GEOSCIENCE CHARACTERIZATION STUDIES (66 88 11 1) ISBN 92-64-13166-3 FF220 US$48.50 £26.00 DM95 .... copy(ies) Volume 4 - ENGINEERING (66 88 12 1) ISBN 92-64-13167-1 FF170 US$37.50 £20.00 DM74 .... copy(ies) Volume 5 - DISPERSAL OF RADIONUCLIDES IN THE OCEANS: MODELS, DATA SETS AND REGIONAL DESCRIPTIONS (66 88 13 1) ISBN 92-64-13168-X ' FF280 US$62 00 £33.00 DM121 .... copy(ies) Volume 6 - DEEP-SEA BIOLOGY, RADIOLOGICAL PROCESSES AND RADIOBIOLOGY (66 88 14 1) ISBN 92-64-13169-8 FF150 US$33.00 £18.00 DM65 copy(ies) Volume 7 - REVIEW OF LABORATORY INVESTIGATIONS OF RADIONUCLIDES MIGRATION THROUGH DEEP-SEA SEDIMENTS (66 88 15 1) ISBN 92-64-13170-1 FF190 US$42.00 £22.50 DM82 ...
    [Show full text]
  • Understanding and Predicting the Gulf of Mexico Loop Current Critical Gaps and Recommendations
    THE NATIONAL ACADEMIES PRESS This PDF is available at http://nap.edu/24823 SHARE Understanding and Predicting the Gulf of Mexico Loop Current Critical Gaps and Recommendations DETAILS 110 pages | 7 x 10 | PAPERBACK ISBN 978-0-309-46220-4 | DOI 10.17226/24823 CONTRIBUTORS GET THIS BOOK Committee on Advancing Understanding of Gulf of Mexico Loop Current Dynamics; Gulf Research Program; National Academies of Sciences, Engineering, and Medicine FIND RELATED TITLES Visit the National Academies Press at NAP.edu and login or register to get: – Access to free PDF downloads of thousands of scientific reports – 10% off the price of print titles – Email or social media notifications of new titles related to your interests – Special offers and discounts Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the National Academies Press. (Request Permission) Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved. Understanding and Predicting the Gulf of Mexico Loop Current Critical Gaps and Recommendations Understanding and Predicting the Gulf of Mexico Loop Current: Critical Gaps and Recommendations Committee on Advancing Understanding of Gulf of Mexico Loop Current Dynamics Gulf Research Program A Consensus Study Report of PREPUBLICATION COPY – Uncorrected Proofs Copyright National Academy of Sciences. All rights reserved. Understanding and Predicting the Gulf of Mexico Loop Current Critical Gaps and Recommendations THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001 This activity was supported by the Gulf Research Program Fund. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
    [Show full text]
  • The Evolution and Demise of North Brazil Current Rings*
    VOLUME 36 JOURNAL OF PHYSICAL OCEANOGRAPHY JULY 2006 The Evolution and Demise of North Brazil Current Rings* DAVID M. FRATANTONI Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts PHILIP L. RICHARDSON Department of Physical Oceanography, Woods Hole Oceeanographic Institution, and Associated Scientists at Woods Hole, Woods Hole, Massachusetts (Manuscript received 27 May 2004, in final form 26 October 2005) ABSTRACT Subsurface float and surface drifter observations illustrate the structure, evolution, and eventual demise of 10 North Brazil Current (NBC) rings as they approached and collided with the Lesser Antilles in the western tropical Atlantic Ocean. Upon encountering the shoaling topography east of the Lesser Antilles, most of the rings were deflected abruptly northward and several were observed to completely engulf the island of Barbados. The near-surface and subthermocline layers of two rings were observed to cleave or separate upon encountering shoaling bathymetry between Tobago and Barbados, with the resulting por- tions each retaining an independent and coherent ringlike vortical circulation. Surface drifters and shallow (250 m) subsurface floats that looped within NBC rings were more likely to enter the Caribbean through the passages of the Lesser Antilles than were deeper (500 or 900 m) floats, indicating that the regional bathymetry preferentially inhibits transport of intermediate-depth ring components. No evidence was found for the wholesale passage of rings through the island chain. 1. Introduction ration from the NBC, anticyclonic rings with azimuthal speeds approaching 100 cm sϪ1 move northwestward a. Background toward the Caribbean Sea on a course parallel to the The North Brazil Current (NBC) is an intense west- South American coastline (Johns et al.
    [Show full text]
  • Chapter 2: Ocean Station Data (Osd), Low-Resolution Ctd, Low-Resolution Expendable Xctd, and Plankton
    NOAA Atlas NESDIS 72 WORLD OCEAN DATABASE 2013 Timothy P. Boyer, John I. Antonov, Olga K. Baranova, Carla Coleman, Hernan E. Garcia, Alexandra Grodsky, Daphne R. Johnson, Ricardo A. Locarnini, Alexey V. Mishonov, Todd D. O'Brien, Christopher R. Paver, James R. Reagan, Dan Seidov, Igor V. Smolyar, Melissa M. Zweng Editor: Sydney Levitus Technical Editor: Alexey Mishonov National Oceanographic Data Center Ocean Climate Laboratory Silver Spring, MD September 2013 U.S. DEPARTMENT OF COMMERCE Penny S. Pritzker, Secretary National Oceanic and Atmospheric Administration Kathryn D. Sullivan, Acting Under Secretary of Commerce for Oceans and Atmosphere National Environmental Satellite, Data, and Information Service Mary E. Kicza, Assistant Administrator Additional copies of this publication, as well as information about NODC data holdings and services, are available upon request directly from NODC. National Oceanographic Data Center User Services Team NOAA/NESDIS E/OC1 SSMC-3, 4th Floor 1315 East-West Highway Silver Spring, MD 20910-3282 Telephone: (301) 713-3277 Fax: (301) 713-3302 E-mail: [email protected] NODC home page: http://www.nodc.noaa.gov/ For updates on the data, documentation and additional information about WOD13 please refer to: http://www.nodc.noaa.gov/OC5/indprod.html This publication should be cited as: Boyer, T.P., J.I. Antonov, O.K. Baranova, C. Coleman, H.E. Garcia, A. Grodsky, D.R. Johnson, R.A. Locarnini, A.V. Mishonov, T.D. O'Brien, C.R. Paver, J.R. Reagan, D. Seidov, I.V. Smolyar, M.M. Zweng, 2013, World Ocean Database 2013. Sydney Levitus, Ed.; Alexey Mishonov, Technical Ed.; NOAA Atlas NESDIS 72, 209 pp.
    [Show full text]