This document provides an overview of oceanography, including definitions, key topics, and methods. It discusses how oceanography is an interdisciplinary field that studies the physics, chemistry, biology, and geology of oceans. Key methods mentioned include collecting data from ships, moorings, autonomous vehicles, and satellites. Ocean circulation, seafloor mapping, and geographic information systems are highlighted as important areas of focus. Several international organizations that contribute to oceanographic research are also summarized.

1. An Introduction to Oceanography
Lecture 2 – MR1008

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Definition
• The study of the ocean, embracing and
integrating all knowledge pertaining to the
ocean's physical boundaries, the
chemistry and physics of sea water, and
marine biology.
www.weather.com/glossary/o.html

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Definition
• The scientific study and exploration of the
oceans and seas in all their aspects,
including all processes in the oceans and
interactions and relations with Earth.
www.reefed.edu.au/glossary/o.html

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Oceanography - summary
• Oceanography is the study of the deep
sea and shallow coastal oceans: their
biology, chemistry, geology and physics
together make oceanography a richly
interdisciplinary science.

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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

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Origins of Oceanography
• The scientific ancestors of oceanographers
range widely
• Physical oceanography harks back to the polar
explorers of the 19th Century and the physicists
who developed the study of flowing fluids.
• Techniques of physics and applied mathematics
are used by physical oceanographers for the
study of the physical ocean and climate.
• An understanding of physics has yielded
significant contributions to biology, chemistry
and geophysics, where understanding at the
molecular level is sometimes the key to
discovery.

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Origins of Oceanography
• Biological oceanographers were
naturalists cataloguing the life-forms
of the sea
• The Geology and Geophysics of the
ocean owes much to ideas of plate
tectonics, verified 'at sea' by the
magnetic striping of seafloor that
emerges from spreading center
ridges, as recently as the 1960s

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Copyright Skinner & Porter 1987

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Origins of Oceanography
Chemical oceanography developed
• in part as a service to biology, through analyses of
nutrients and dissolved gases relating to life in the
sea.
• Chemistry in oceanography also developed through
simple curiosity about the circulation: trace chemicals
(dissolved gases, natural nutrients, radioactive
products of nuclear weapons testing, trace metals) are
transported with the ocean circulation and exchanged
with seabed and atmosphere
• This is a science in its own right providing a detailed
picture of the ocean circulation that cannot be
obtained from direct measurement of currents.

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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.

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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

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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.

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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

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Some Facts
• The oceans cover 7/10 of the Earth's
surface.
• Together with the atmosphere and the
'fresh-water' sphere they make up 'fluid'
Earth.
• Much of the biomass...the mass of living
plants and animals...lives in the oceans,
far more than on land!

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• 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 ½ of the primary production
of oxygen from photosynthesis, by all life
on Earth, occurs in the sea. Roughly ½ of
that occurs in the productive, shallow
ocean near land.
Some Facts

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Some More Facts
• Coastal oceanography is also of great
importance
• 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 e.g. population increase,
pollution, ballast water exchange

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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.

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

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• 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.
What does Oceanography Entail?

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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

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• 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)
What does Oceanography Entail?

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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.

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• 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
What does Oceanography Entail?

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• 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.
What does Oceanography Entail?

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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.

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Ship, Type, Specifications &
Location
R/V Roger RevelleBuilt: 1996
Length: 273'
Beam: 52'5"
Draft (max): 17'
Gross Tonnage: 3,180 long tons
Displacement: 3,512 long tons
Crew: 22
Scientific berthing: 37
Motors: Two 3,000 hp Propulsion General Electric
Bow Thruster: 1,180 hp Azimuthing jet
Propulsion: Two 3,000 hp Z-Drive Lips
Water Capacity: 12,000 gal
Incinerator: YesFuel consumption: 4,400 gal/day (transit)
Speed, Cruising: 12 knots
Speed, Maximum: 15 knots
Speed, Minimum: variable to 0, any direction
Endurance: 52 days at 12 knots (fuel)
Range: 15,000 at 12 knots (fuel)
Fuel capacity: 227,500 (planning)

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• Oceanography Committee (OCC)
• Chair: Einar Svendsen Area 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
ICES

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• 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
ICES

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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.

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IFREMER

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

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Seafloor
• Data collection: echo sounders and sonar

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Satellites - sea surface temperature
•This image is a close up of part of the
Gulf Stream.
•AVHRR sensor (Advanced Very High
Resolution Radiometer) carried on a
NOAA satellite (Nation Oceanic and
Atmospheric Administration)
•In this image the core of the Gulf
Stream ranges between 25 and 28 deg
C (77 and 82 F).
•The yellow water below the stream is
about 23 deg C (73 F) and the green
water off Long Island is about 14 deg C
(57 F).
•The blue water around Nova Scotia is
about 5 deg C (41 F)! The black line
shows where the ocean is 1000m
deep, (water shoreward of this line is
less than 1000 meters deep and water
seaward of this line is more than 1000
meters deep).

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Circulation
• Ocean circulation is the large scale
movement of waters in the ocean basins.
• Winds drive surface circulation, and the
cooling and sinking of waters in the polar
regions drive deep circulation
(Thermohaline).
• Surface circulation carries the warm upper
waters poleward from the tropics.

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• Heat is dispersed along the way from the
waters to the atmosphere
• At the poles, the water is further cooled
during winter, and sinks to the deep
ocean. This is especially true in the North
Atlantic and along Antarctica
• Deep ocean water gradually returns to the
surface nearly everywhere in the ocean.
Circulation cont..

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Circulation cont..
• Once at the surface it is carried back to
the tropics, and the cycle begins again.
The more efficient the cycle, the more
heat is transferred, and the warmer the
climate.
• Due to the rotation of the Earth, currents
are deflected to the right in the northern
hemisphere and to the left in the southern
hemisphere. This effect is known as the
"Coriolis force."
• The deflection leads to highs and lows of
sea level directly proportional to the speed
of the surface currents.

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Circulation cont..
• The changes in sea level due to currents are the
ocean topography that is observed by
TOPEX/Poseidon.
• Observations of ocean topography and a
knowledge of the Coriolis force permit scientists to
map ocean currents using data from the satellite.
Every ten days TOPEX/Poseidon produces maps
of the currents everywhere in the ocean.

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Deep Sea Circulation
• Thermohaline circulation refers to the
deepwater circulation of the oceans and is
primarily caused by differences in density
between the waters of different regions.
• It is mainly a convection process where
cold, dense water formed in the polar
regions sinks and flows slowly toward the
equator.
• Most of the deep water acquires its
characteristics in the Antarctic region and
in the Norwegian Sea.

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• Antarctic bottom water is the densest and
coldest water in the ocean depths. It forms
and sinks just off the continental slope of
Antarctica and drifts slowly along the
bottom as far as the middle North Atlantic
Ocean, where it merges with other water.
• The circulation of ocean waters is vitally
important in dispersing heat energy around
the globe. In general, heat flows toward
the poles in the surface currents, while the
displaced cold water flows toward the
equator in deeper ocean layers.
Deep Sea Circulation

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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

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Data Collection and Management
• ICES oceanographic data in ODV generic
format
ICES Oceanographic Database and Services

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GIS
Undersea with GIS – Dawn Wright (ed.)
ESRI Press

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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)

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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

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Journals
ICES Journal of Marine Science
The ICES Journal of Marine Science publishes articles, short communications, and critical reviews that contribute to our scientific
understanding of marine systems and the impact of human activities.
The Journal serves as a foundation for scientific advice across the broad spectrum of management and conservation issues related
to the marine environment.
Oceanography, marine habitats, living resources, and related management topics constitute the key elements of papers eligible
for publication. Integrated studies that bridge gaps between traditional disciplines are particularly welcome.
The scope of the Journal has been broadened to include economic, social, and public administration studies to the extent that they
are directly related to management of the seas and are of general interest to marine scientists.
Proceedings of ICES-sponsored symposia constitute an integral part of the Journal and observe the standards set for regular papers.
History

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