EAS212 THE OCEANS

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EAS212 THE OCEANS

• Winter Term 2009
• Dr. Andrew Bush

Photo acknowledgements Wade McGillis, SOLAS
Summer School, 2003
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What is Oceanography

• Ocean comes from Greek for the Seas
• Graphy comes from Greek for a descriptive Science
• This might imply that oceanography is the science
  of describing the marine environment
• This is true, but oceanography is now so much
  more
• It might be called the study of all aspects of
  the marine environment

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What is Oceanography

• Or, Studying the processes of the ocean
• Physics, chemistry, biology, geology
• We will concentrate on the Physical and Chemical
  aspects in this course
• Physical Oceanography wave dynamics, currents,
  ocean-atmosphere interactions, oceans role in
  climate
• Chemical Oceanography dissolved solids and
  gasses in the ocean, composition of water

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Why Study the Physics and Chemistry of the Ocean?

• Could consider 3 main themes
• The oceans as a source of food
• We use the oceans
• Oceans influence weather and climate
• These themes influence
• What we measure
• How measurements are made
• Geographical areas of interest
• Interest in different process of different scale
• Local, regional, global

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Different Time and Space Scales
time
Repeat Trans-basin Sections
centuries
decadal
Shipboard Time-Series
Inter-annual
Moored Time-Series
VOS surface pCO2
Remote sensing
seasonal
daily
Process Studies
hourly
space
Ocean Basin
1 m2
1 km2
Globe
Regional (106 km2)
Thanks to Tom Dickey
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What are the sources of information about
physical variables?

• What instruments are used for measuring each
  variable?
• What are their accuracy and limitations?
• What historic data exist?
• What platforms are used? Satellites, ships,
  drifters, moorings?

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What processes are important?

• Heat storage and transport in the oceans
• The exchange of heat with the atmosphere and the
  role of the ocean in climate
• Wind and thermal forcing of the surface mixed
  layer
• The wind-driven circulation
• The dynamics of ocean currents

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What processes are important?

• The formation of water types and masses
• The deep circulation
• Equatorial dynamics and El Niño
• Waves in the ocean, both surface and internal
• Waves in shallow water and coastal processes

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Integrated Picture

• To study the ocean, we will use theory,
  observations and numerical models
• None are sufficient by themselves
• Ocean processes and non-linear and turbulent, so
  theories are simplified
• Observations are sparse in time and space, so
  cannot completely describe the oceans
• Numerical models are approximations of the real
  system, and cant represent all small scale
  processes