WOODS HOLE OCEANOGRAPHIC INSTITUTION Deep-Diving
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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. -
38. Effect of Axial Magma Chambers Beneath Spreading Centers on the Compositions of Basaltic Rocks
38. EFFECT OF AXIAL MAGMA CHAMBERS BENEATH SPREADING CENTERS ON THE COMPOSITIONS OF BASALTIC ROCKS James H. Natland, Scripps Institution of Oceanography, La Jolla, California ABSTRACT Ferrobasalts are among a range of basalt types erupted over large, shallow, axial magma chambers beneath the East Pacific Rise crest near 9°N, and the Galapagos Rift near 86°W. Geological and geo- chemical evidence indicates that they evolve in small, isolated magma bodies either in conduit systems over the chambers, or in the solidify- ing walls of the magma chamber flanks away from the loci of fissure eruptions. The chambers act mainly as buffers in which efficient mix- ing ensures that a uniform average, moderately fractionated parent is supplied to the range of magma types erupted at the sea floor. For- mation of ferrobasalts in isolated magma bodies prevents them from mixing directly with primitive olivine tholeiite supplied to the base of the East Pacific Rise magma chamber at 9°N. Rises with abundant ferrobasalts may have magma chambers with broad, flat tops over which eruptions occur in wide, probably struc- turally unstable rift zones. Rises without ferrobasalts may have magma chambers with tapered tops which persistently constrain eruptions to narrow fissure zones, preventing formation of isolated shallow magma bodies where ferrobasalts can evolve. Formation of a flat-topped, rather than a tapered, magma chamber may reflect a high rate of magma supply relative to spreading rate. Steady-state compositions can be approached in magma cham- bers, probably approximating the least-fractionated typical lavas erupted above them. On this basis, the bulk magma composition in the chamber beneath the Galapagos Rift has become more iron-rich through time, a consequence of magma migration eastward down the rift as it shoaled to the west under the influence of the Galapagos Island hot spot. -
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SCIENTIFIC AMERICAN FRONTIERS PROGRAM #1503 "Going Deep" AIRDATE: February 2, 2005 ALAN ALDA Hello and welcome to Scientific American Frontiers. I'm Alan Alda. It's said that the oceans, which cover more than two thirds of the earth's surface, are less familiar to us than the surface of the moon. If you consider the volume of the oceans, it's actually more than ninety percent of the habitable part of the earth that we don't know too much about. The main reason for our relative ignorance is simply that the deep ocean is an absolutely forbidding environment. It's pitch dark, extremely cold and with pressures that are like having a 3,000-foot column of lead pressing down on every square inch -- which does sound pretty uncomfortable. In this program we're going to see how people finally made it to the ocean floor, and we'll find out about the scientific revolutions they brought back with them. We're going to go diving in the Alvin, the little submarine that did so much of the work. And we're going to glimpse the future, as Alvin's successor takes shape in a small seaside town on Cape Cod. That's coming up in tonight's episode, Going Deep. INTO THE DEEP ALAN ALDA (NARRATION) Woods Hole, Massachusetts. It's one of the picturesque seaside towns that draw the tourists to Cape Cod each year. But few seaside towns have what Woods Hole has. For 70 years it's been home to the Woods Hole Oceanographic Institution — an organization that does nothing but study the world's oceans. -
Dissolved and Particulate Organic Carbon in Hydrothermal Plumes from the East Pacific Rise, 91500N
Deep-Sea Research I 58 (2011) 922–931 Contents lists available at ScienceDirect Deep-Sea Research I journal homepage: www.elsevier.com/locate/dsri Dissolved and particulate organic carbon in hydrothermal plumes from the East Pacific Rise, 91500N Sarah A. Bennett a,n, Peter J. Statham a, Darryl R.H. Green b, Nadine Le Bris c, Jill M. McDermott d,1, Florencia Prado d, Olivier J. Rouxel e,f, Karen Von Damm d,2, Christopher R. German e a School of Ocean and Earth Science, National Oceanography Centre, Southampton SO14 3ZH, UK b National Environment Research Council, National Oceanography Centre, Southampton SO14 3ZH, UK c Universite´ Pierre et Marie Curie—Paris 6, CNRS UPMC FRE3350 LECOB, 66650 Banyuls-sur-mer, France d University of New Hampshire, Durham, NH 03824, USA e Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA f Universite´ Europe´enne de Bretagne, European Institute for Marine Studies IUEM, Technopoleˆ Brest-Iroise, 29280 Plouzane´, France article info abstract Article history: Chemoautotrophic production in seafloor hydrothermal systems has the potential to provide an Received 19 November 2010 important source of organic carbon that is exported to the surrounding deep-ocean. While hydro- Received in revised form thermal plumes may export carbon, entrained from chimney walls and biologically rich diffuse flow 23 June 2011 areas, away from sites of venting they also have the potential to provide an environment for in-situ Accepted 27 June 2011 carbon fixation. In this study, we have followed the fate of dissolved and particulate organic carbon Available online 3 July 2011 (DOC and POC) as it is dispersed through and settles beneath a hydrothermal plume system at 91500N Keywords: on the East Pacific Rise. -
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. -
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 -
Exploration of the Deep Gulf of Mexico Slope Using DSV Alvin: Site Selection and Geologic Character
Exploration of the Deep Gulf of Mexico Slope Using DSV Alvin: Site Selection and Geologic Character Harry H. Roberts1, Chuck R. Fisher2, Jim M. Brooks3, Bernie Bernard3, Robert S. Carney4, Erik Cordes5, William Shedd6, Jesse Hunt, Jr.6, Samantha Joye7, Ian R. MacDonald8, 9 and Cheryl Morrison 1Coastal Studies Institute, Louisiana State University, Baton Rouge, Louisiana 70803 2Department of Biology, Penn State University, University Park, Pennsylvania 16802-5301 3TDI Brooks International, Inc., 1902 Pinon Dr., College Station, Texas 77845 4Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 5Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave., Cambridge, Massachusetts 02138 6Minerals Management Service, Office of Resource Evaluation, New Orleans, Louisiana 70123-2394 7Department of Geology, University of Georgia, Athens, Georgia 30602 8Department of Physical and Environmental Sciences, Texas A&M – Corpus Christi, Corpus Christi, Texas 78412 9U.S. Geological Survey, 11649 Leetown Rd., Keameysville, West Virginia 25430 ABSTRACT The Gulf of Mexico is well known for its hydrocarbon seeps, associated chemosyn- thetic communities, and gas hydrates. However, most direct observations and samplings of seep sites have been concentrated above water depths of approximately 3000 ft (1000 m) because of the scarcity of deep diving manned submersibles. In the summer of 2006, Minerals Management Service (MMS) and National Oceanic and Atmospheric Admini- stration (NOAA) supported 24 days of DSV Alvin dives on the deep continental slope. Site selection for these dives was accomplished through surface reflectivity analysis of the MMS slope-wide 3D seismic database followed by a photo reconnaissance cruise. From 80 potential sites, 20 were studied by photo reconnaissance from which 10 sites were selected for Alvin dives. -
Deep-Tow Studies of the Structure of the Mid-Atlantic Ridge Crest Near Lat 37°N
Deep-tow studies of the structure of the Mid-Atlantic Ridge crest near lat 37°N KEN C. MACDONALD* Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, La Jolla, California 92093 BRUCE P. LUYENDYK Department of Geological Sciences, University of California, Santa Barbara, California 93106 This article is one of a series appearing in the April and May issues of the Geological Society of America Bulletin on the scientific results of Project FAMOUS. These studies were undertaken in the axial area of the Mid-Atlantic Ridge between approximately 36°30' and 37°N latitudes. ABSTRACT large faulted blocks toward nearby fracture Le Pichon, 1974). We discuss here the de- zones suggests that spreading-center tec- tailed structure and evolution of the rift val- A detailed study of the structure of the tonics is affected by fracture-zone tectonics leys between fracture zones A and B (rift Mid-Atlantic Ridge median valley and rift throughout the length of the rift in the valley 2) and B and C (rift valley 3) and the mountains near lat 37°N (FAMOUS) was FAMOUS area. Both the crustal accretion rift mountains in these areas. Fine-scale conducted using a deep-tow instrument zone and transform fault zone are narrow, deep-tow studies of the inner floor of rift package. The median valley may have either only 1 to 2 km wide, over short periods of valley 2 are discussed by Luyendyk and a very narrow inner floor (1 to 4 km) and time. In the course of millions of years, how- Macdonald (1977). -
NATIONAL OCEANOGRAPHIC LABORATORY SYSTEM %Vas
UNIVERSITY - NATIONAL OCEANOGRAPHIC LABORATORY SYSTEM ALVIN REVIEW COMMITTEE Summary Report of the June 26, 27, 1991 Meeting Carriage House Woods Hole Oceanographic Institution Woods Hole, MA Minutes of the Meeting APPENDICES I. ALVIN Review Committee Roster II. Agenda III. Report on ALVIN Operations, 1990-1991 IV. Letter on Archiving Policy for ALVIN data and records V. 1991 Dive Requests by Region VI. Summary of 1992 Dive Requests VII. Opportunities for Oceanographic Research, DSV ALVIN, 1992 VIII. Rules for Review of ALVIN Dive Requests it as 111K . "? • %Vas- IILALtr CE D AUG 1 . ) 1991 I 1 UNOLS OFFICE ALVIN Review Committee Minutes of Meeting June 26, 27, 1991 Carriage House Woods Hole Oceanographic Institution Woods Hole, MA OPENING THE MEETING The meeting was called at 8:00 a.m. by Feenan Jennings, ARC Chair. Committee members, funding agency representatives from NOAA, NSF and ONR, WHOI personnel and UNOLS Office staff present for all or part of the meeting: ALVIN Review Committee Agency Representatives Feenan Jennings, Chair David Duane, NOAA Casey Moore Don Heinrichs, NSF Doug Nelson Keith Kaulum, ONR Mary Scranton Gary Taghon Karen Von Damm Dick Pittenger, WHOI member WHOI UNOLS Office Craig Dorman Bill Barbee Barrie Walden Jack Bash Don Moller Annette DiSilva Rick Chandler Mary D'Andrea The ALVIN Review Committee Roster is Appendix I. Craig Dorman, Director, WHOI, welcomed the ALVIN Review Committee and introduced Dick Pittenger, whom he had earlier named as the WHOI (operating institution ex-officio) member on the ARC. Dr. Dorman reiterated WHOI's strong commitment to continue to manage and operate ALVIN in support of the United States' oceanographic program. -
Ocean-Bottom Seismograph Observations on the Mid-Atlantic Ridge Near Lat 37°N
Ocean-bottom seismograph observations on the Mid-Atlantic Ridge near lat 37°N T.J.G. FRANCIS* Cooperative Institute for Research in Environmental Sciences, University of ColoradolNOAA, Boulder, Col- orado 80309 I. T. PORTER Institute of Oceanographic Sciences, Blacknest, Brimpton, Reading, RG7 4TJ England J. R. McGRATH U.S. Naval Research Laboratory, Washington, D.C. 20390 This article is one of a series appearing in the April and May issues of the Geological Society of America Bulletin on the scientific results of Project FAMOUS. These studies were undertaken in the axial area of the Mid-Atlantic Ridge between approximately 36°30' and 37°N latitudes. ABSTRACT 200 Hz. The tape speed of the recording system used by the ocean-bottom seismographs set an upper limit of about 40 Hz to Ocean-bottom seismographs were deployed twice in the FA- the frequencies recorded. It was decided to retain the original hyd- MOUS area in 1973. Few earthquakes were observed on the first rophones of the seismographs as well to be able to compare the per- occasion, but 515 were recorded on the second with magnitudes formance of the two systems. Since only four data channels can be ranging from 0 to 2.5. These occurred both in the median valley recorded in each ocean-bottom seismograph, the H-58 hydrophone and in the fracture zone adjacent to the instruments. The latter was substituted for one of the horizontal seismometers. Thus dur- events have been interpreted as activity along a single Riedel frac- ing the October 1973 deployment, each instrument recorded the ture cutting obliquely across the trend of the fracture zone. -
Coastal Upwelling Revisited: Ekman, Bakun, and Improved 10.1029/2018JC014187 Upwelling Indices for the U.S
Journal of Geophysical Research: Oceans RESEARCH ARTICLE Coastal Upwelling Revisited: Ekman, Bakun, and Improved 10.1029/2018JC014187 Upwelling Indices for the U.S. West Coast Key Points: Michael G. Jacox1,2 , Christopher A. Edwards3 , Elliott L. Hazen1 , and Steven J. Bograd1 • New upwelling indices are presented – for the U.S. West Coast (31 47°N) to 1NOAA Southwest Fisheries Science Center, Monterey, CA, USA, 2NOAA Earth System Research Laboratory, Boulder, CO, address shortcomings in historical 3 indices USA, University of California, Santa Cruz, CA, USA • The Coastal Upwelling Transport Index (CUTI) estimates vertical volume transport (i.e., Abstract Coastal upwelling is responsible for thriving marine ecosystems and fisheries that are upwelling/downwelling) disproportionately productive relative to their surface area, particularly in the world’s major eastern • The Biologically Effective Upwelling ’ Transport Index (BEUTI) estimates boundary upwelling systems. Along oceanic eastern boundaries, equatorward wind stress and the Earth s vertical nitrate flux rotation combine to drive a near-surface layer of water offshore, a process called Ekman transport. Similarly, positive wind stress curl drives divergence in the surface Ekman layer and consequently upwelling from Supporting Information: below, a process known as Ekman suction. In both cases, displaced water is replaced by upwelling of relatively • Supporting Information S1 nutrient-rich water from below, which stimulates the growth of microscopic phytoplankton that form the base of the marine food web. Ekman theory is foundational and underlies the calculation of upwelling indices Correspondence to: such as the “Bakun Index” that are ubiquitous in eastern boundary upwelling system studies. While generally M. G. Jacox, fi [email protected] valuable rst-order descriptions, these indices and their underlying theory provide an incomplete picture of coastal upwelling. -
The Project Investigators Will Comply with the Data Management And
Data Management Plan Data Policy Compliance: The project investigators will comply with the data management and dissemination policies described in the NSF Award and Administration Guide (AAG, Chapter VI.D.4) and the NSF Division of Ocean Sciences Sample and Data Policy. Pre-Cruise Planning: Pre-cruise planning will occur through email and teleconFerences. The cruises will utilize a deep submergence vehicle (DSV Alvin, Woods Hole Oceanographic Institution). Preliminary dive plans will be written prior to the cruise, and updated and amended prior to each dive based on cruise events. Cruise event logging: Detailed dive reports For each Alvin dive will be digitally compiled as MicrosoFt Word documents during the cruise. Each dive report will include site inFormation, times oF launch and recovery, sampling events, and watch-stander logs. These, along with each dive plan, participant inFormation, and samples logs will be compiled into a cruise report at the conclusion oF the cruise and shared among the cruise party. Description of Data Types This project will produce observational datasets through the ship's underway sensors, DSV Alvin sensors and cameras, deployed autonomous chemistry sensors, and derived From analysis oF collected biological specimens. Observational data will be collected on research cruise at the East PaciFic Rise planned to take place during Jan-April oF two diFFerent years. Cruise underway data: Standard underway data collected along the ship’s track (e.g., sea surFace temperature, salinity, etc.). File types: .csv ASCII Files; Repository: BCO-DMO and the Rolling Deck to Repository (R2R). Alvin data: Routine sensor data (e.g., temperature), video, and images collected by the DSV Alvin, as well as dive event logs, are made available through WHOI dives FrameGrabber system at http://4dgeo.whoi.edu/alvin and archived at the National Deep Submergence Facility (NDSF) at Woods Hole Oceanographic Institution.