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Introduction to Oceanography

Introduction to Oceanography. Definition.

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Introduction to Oceanography

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  1. Introduction to Oceanography

  2. Definition • Scientific discipline concerned with all aspects of the world's oceans and seas, including their physical and chemical properties, origin and geology, and life forms. Research entails sampling seawater and marine life, remote sensing of oceanic processes with aircraft and satellites, and exploration of the seafloor. Oceanography aids in predicting weather and climate, in exploitation of the Earth's resources, and in understanding the effects of pollutants. http://www.merriam-webster.com/dictionary/oceanography

  3. Why is Oceanography important? • The importance of the oceans to physical climate, food supplies and biological stability • An extra dimension to human activity And………. • Long-term habitability of Earth

  4. Fields of Oceanography • Physical oceanographers • study the tides, currents, waves, particle transportation, erosion, ocean-climate relationship and the transmission of light and sound waves through the water. Techniques of physics and applied mathematics are used by physical oceanographers for the study of the physical ocean and climate.

  5. Fields of Oceanography • Biological oceanographers • study the interactions of marine animals, plants and micro-organisms. They are also interested in the numbers of organisms as well as how they adapt to their environment.

  6. Fields of Oceanography • Geologic oceanographers • study plate tectonics, processes which form the seafloor, canyons and valleys, seismic activities which cause tsunamis, core sampling to study the geologic history of the seafloor as well as ocean circulation and climates.

  7. Fields of Oceanography • Chemical oceanographers • Study the composition of seawater, its processes, cycles, and the chemical interaction of seawater with the atmosphere and sea floor. analysis of seawater components, the effects of pollutants, and the impacts of chemical processes on marine organisms. They may also use chemistry to understand how ocean currents move seawater around the globe and how the ocean affects climate or to identify potentially beneficial ocean resources such as natural products that can be used as medicines.

  8. Living Machine • Together with the atmosphere, continents and ice-cover (the 'cryosphere'), they form a working machine, driven mostly by energy from the sun. • Lesser amounts of energy derive from tides raised by the moon and sun and planets, and heat from the Earth's interior.

  9. Oceanographers and Oceans • Oceanographers aim their work at both practical problems and basic scientific discovery • Oceans : • provide threats; • a bountiful diversity of food • are the reservoir of our water supply • most of the heat and carbon of the climate system • are the source of roughly ½ the respired oxygen of the biosphere, • contain most of the remaining undiscovered natural pharmaceuticals

  10. Oceanographers and Oceans • Study of ocean life provides models for research in human illness, for example using the giant, accessible neurons of the squid. • Techniques of classical physics are joined with modern instrumentation and computers.

  11. A Young Science • Although oceanography is a relatively young science • It is the natural setting to ask fundamental questions about the development of life, and the behavior (or misbehavior) of global climate

  12. Some Interesting Facts • The oceans cover 70% of the Earth's surface. • Much of the biomass...the mass of living plants and animals...lives in the oceans, far more than on land and we are still discovering more species every year!

  13. More Interesting Facts • Photosynthesis of the phytoplankton (the 'grass' of the seas) and respiration of zooplankton and larger animals (the 'cows' of the sea) are important to the global chemical balance of our oxygen-rich world • Very roughly 50% of the primary production of oxygen from photosynthesis, by all life on Earth, occurs in the sea. Roughly 50% of that occurs in the productive, shallow ocean near land.

  14. Even More Facts • About 25% of global primary productivity (photosynthesis by plant life) occurs in the ocean near the coasts, and that is about one-half of the total productivity of the world ocean. 80 to 90% of the world fish catch occurs in the coastal ocean. • Today these shallow-water ocean regions are under great stress from population increase, pollution, ballast water exchange and other major issues.

  15. What does Oceanography Entail? • Until the 1970s the normal oceanographic expedition (time at sea) involved bringing back samples of water from the deep ocean for analysis using simple measurements: • reversing thermometers and Nansen bottles lowered on steel cables, and triggered by dropping a weight (the 'messenger') down the wire • plankton tows in simple mesh nets • small coring devices • bottom dredges.

  16. Nansen Bottle A Nansen bottle coming out of the water on a nearly mirror smooth sea.

  17. What does Oceanography Entail? • Today with electronics and computers many more things can be measured. • Physical variables like temperature and salinity are observed in this way, and there are new probes being designed that will allow electronic measurement of many chemical and biological variables.

  18. What does Oceanography Entail? • Seismology and sub-seabed geophysics are being explored using 'underwater observatories‘ • Moorings, with steel or Kevlar cable extending from near the ocean surface to its bottom, have many instruments to record observations internally

  19. What does Oceanography Entail? • Autonomous undersea vehicles (AUVs) propel themselves or drift with currents for years at a time. • Satellites - Satellite oceanography is combined with other observations and with computer modelling of ocean/atmosphere circulation to give a 'best-fit' assimilation of the complete circulation. (see Regional Satellite Oceanography – Serge Victorov – Taylor and Francis)

  20. What does Oceanography Entail? • In the Arctic oceanographers use Icebreakers or methods of boring holes in the ice and helicopters and ski-equipped airplanes to do 'sections' across the Arctic, or to set moorings and autonomous vehicles into action. • “Cat-Scans" using fast, small boats towing instruments that 'fly' through the water on a carefully controlled course. Acoustic waves are sent down through the water column, and their reflections off small particles in the water give a complete profile of the ocean velocity, from top to bottom.

  21. What does Oceanography Entail? • Theoretical work in oceanography uses classical physics and many sub-fields of physics: for example the science of 'chaos', which involves the complex behavior of seemingly simple physical systems. • The 'soliton', a fundamental, nonlinear wave that propagates undistorted over great distances, was discovered in oceanography and now is found in fiber-optics cables, and many physical systems

  22. What does Oceanography Entail? • Computers play an intense role in physical oceanography, giving us simulations of waves and circulation based on Newtonian dynamics. • Ocean and atmosphere are coupled together in 'climate models' and 'circulation models'; the computer models become the meeting point for observations, theory and prediction.

  23. WOODS HOLE MASSACHUSETS Woods Hole Oceanographic Institution is the world's largest private, non-profit oceanographic research institution and a global leader in the study and exploration of the ocean. • Their purpose is to: • UNDERSTAND the ocean and its importance to Earth and humanity • EXPLORE the ocean in all its depth and complexity • EDUCATE scientists, students, decision-makers, and the public

  24. WOODS HOLE MASSACHUSETS R/V Atlantis The 274-foot (83 meter) Atlantis, one of the nation's newest research vessels, is specially outfitted for the vehicles of the National Deep Submergence Facility. R/V Knorr A 279-foot (84.5-meter) vessel, Knorr can stay at sea for up to eight weeks. It is equipped with sophisticated navigation and communication systems and can accommodate a wide variety of scientific projects. R/V Tioga Designed for day trips to coastal waters, 60-foot Tioga can cruise at 20 knots and has a range of 350 miles.

  25. WOODS HOLE MASSACHUSETS R/V Neil Armstrong In May 2010, the Office of Naval Research selected WHOI to operate one of two new Armstrong-Class research vessels. R/V Neil Armstrongis scheduled for completion by 2014 and to begin science operations by 2015.

  26. Alvinis a 3-person research submarine that takes scientists deep into the ocean. Since its launch in 1964, the Alvin has enabled more than 2,500 scientists, engineers, and observers to visit the floor of the deep sea. Jason/Medeais a remotely operated vehicle (ROV) system designed and built by WHOI’s Deep Submergence Laboratory. A 10-kilometer (6-mile) tether relays electrical power, control signals, data and live video imagery between a surface ship and the vehicle. The autonomous underwater vehicle (AUV) Sentryis following in the wake of its predecessor, ABE, as a fully autonomous underwater vehicle capable of exploring the ocean down to 4,500 meters (14,764 feet) depth. The DEEPSEA CHALLENGERis a one-person human-occupied vehicle (HOV) that was built to descend to and explore the deepest places in the ocean. In March 2012, James Cameron used it to visit Challenger Deep. One year later, he transferred the vehicle to WHOI, forming a partnership to advance deep-ocean science and exploration.

  27. The HROV will operate in two modes; as an autonomous, or free-swimming, vehicle for wide area surveys (left) and as a tethered, or cabled, vehicle for sampling and other tasks. AUVs are programmable, robotic vehicles that, depending on their design, can drift, drive, or glide through the ocean without real-time control by human operators. REMUS, SeaBED, Sentry, Spray Glider, Slocum Glider Equipped with a variety of sensors, towed vehicles are lowered over the side of a research vessel and pulled through the water at different depths. CAMPER, SeaSoar, TowCam, Video Plankton Recorder

  28. Scripps Institute of Oceanography • At Scripps, observation, measurement, and collection of samples and data are accomplished on a global scale by extensive shipboard, ground, and aerial operations, including remote sensing by satellite and the use of wide-ranging instrument networks.

  29. Scripps Institute of Oceanography R/V Roger RevelleBuilt: 1996Length: 273' Beam: 52'5" Draft (max): 17'Gross Tonnage: 3,180 long tons Displacement: 3,512 long tons Crew: 22Scientific berthing: 37Motors: Two 3,000 hp Propulsion General ElectricBow Thruster: 1,180 hp Azimuthing jetPropulsion: Two 3,000 hp Z-Drive Lips Water Capacity: 12,000 gal Incinerator: YesFuel consumption: 4,400 gal/day (transit)Speed, Cruising: 12 knotsSpeed, Maximum: 15 knotsSpeed, Minimum: variable to 0, any directionEndurance: 52 days at 12 knots (fuel)Range: 15,000 at 12 knots (fuel)Fuel capacity: 227,500 (planning)

  30. ICES • Oceanography Committee (OCC) • Chair: Einar SvendsenArea of responsibility is physical, chemical, and pelagic biological oceanography, especially in relation to the processes relevant to living marine resources and environmental quality. • Responsiblity includes issues such as impacts of climate variability and change, and the quantification of physical, chemical and biological fluxes in coastal, shelf and open ocean areas. • Describe, understand, and quantify the state and variability of the marine environment in terms of its physical, chemical and biological processes

  31. ICES • Understand and quantify the role of climate variability and its implications for the dynamics of the marine ecosystems • Evaluate the ecosystem consequences of contaminants and eutrophication • Develop and improve fisheries assessment tools that utilize environmental information, consider biological and socio-economic interactions and address issues of uncertainty, risk, and sustainability

  32. ICES cont… • Play an active role in the design, implementation, and execution of global and regional research and monitoring programmes • Co-ordinate international monitoring and data management programmes that underpin ongoing ICES core science.

  33. IFREMER

  34. Some Examples • Seafloor • Satellite Oceanography • Circulation and Currents • Geographic Information Systems (GIS)

  35. Other Areas • Ocean Dimensions, Shapes & Bottom Materials • Properties of Salt Water • Geography – patterns and distributions • Water, Salt and Heat budgets • Geology • Deep Sea Fisheries • Coral Reefs

  36. Useful Websites • http://www.mth.uea.ac.uk/ocean/vl/ (WWW Virtual Library) • http://www.tos.org/ (Oceanography Society) • http://www.soc.soton.ac.uk/ (Southampton Oceanography Society) • http://www.soc.soton.ac.uk/GDD/index.html (Ocean Processes) • http://www.esdim.noaa.gov/ocean_page.html (Ocean Resources) • http://oceanworld.tamu.edu/ (OceanWorld) • http://www.bio.gc.ca/welcome-e.html (Bedford Institute) • http://sio.ucsd.edu/ (Scripps Institute) • http://www.mar.dfo-mpo.gc.ca/science/ocean/remotesensing/welcome.html (Remote Sensing) • http://www.phys.ocean.dal.ca/hotlists/Canada.html (Hotlist of Oceanography websites) • http://www.ices.dk/ (ICES)

  37. References • Oceanography, An Illustrated Guide,  Wiley & Sons, New York. edited by Colin Summerhayes and Stephen Thorpe, Eds. 1998 • Science and the Seven Seas: a history of Oceanography, 1650-1900, Margaret Deacon, Academic Press, 1971. • Why We Are Oceanographers, in Collected Works of Henry M. Stommel, Amer. Meteorological Soc. Press, 1995 (reprinted from Oceanography, vol 2, pp 48-54, 1989) • New Eyes on the Oceans, Jennifer Ackerman, National Geographic Magazine, October 2000 • Ocean Sciences At the New Millenium, National Science Foundation, March 2001. • Ocean Circulation - The Open University Press - Butterworth Heinemann • Descriptive Physical Oceanography - G. Pickard and W.Emery - Pergamon • Introductory Physical Oceanography - S. Pond and G.Pickard - Pergamon • Waves, Tides and Shallow-Water Processes - The Open University Press -Butterworth Heinemann

  38. Jobs on Oceanography • Background in • Physics • Mathematics • Chemistry • Biology • Geology... • ……coupled with an intense curiosity about the natural world!

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