MAST602: Advection, transports, budgets

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MAST602 Advection, transports, budgets
Reading Knauss Chapter 4
Flux, transport Radiation, Advection,
Diffusion Conservation of volume Continuity
Conservation of salt Freshwater transport Heat
budget Heat transport
Adapted from Dr. Lynne Talleys SIO class notes
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Transport processes
In lieu of an animation, pretend that this is
animated. (1) The surface heat balance, including
radiation, makes the ocean warmer to the south.
(2) The Gulf Stream flows northward, advectting
warm water. (3) Eddies diffuse the heat.
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Continuity
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Flux and transport

• Transport
• Velocity times concentration integrated (summed)
  over area normal to the velocity
• (same as Flux normal to an area integrated over
  that area.)

• Flux of a property
• Velocity times concentration
• (same as Transport per unit area)

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Transport definitions

• Volume integral of velocity v m3/sec
• Mass integral of density x velocity ?v kg/sec
• Heat integral of heat x velocity ?cpTv
  J/secW
• Salt integral of salt x velocity ?Sv kg/sec
• Freshwater integral of Fwater x velocity
  ?(1-S)v kg/sec
• Chemical tracers integral of tracer x velocity
  ?Cv moles/sec
• Where integral is the over the area normal to
  the velocity
• Flux is just these quantities per unit area

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Conservation of volume, salt and freshwater

• (1) Mass conservation ? oVo - ?i Vi (R AP) -
  AE ? F
• (2) Salt conservation Vi ?i Si Vo ? o So
• (3) F ?i Vi (Si /So - 1) or F ? o Vo (1
  So /Si )
• (4) Also from (2), Vi ?i Si /Sm Vo ? o So / Sm
  where Sm is a mean salinity, so
• (5) F ?i Vi (1- Si /Sm ) - ? o Vo (1 - So / Sm)
  which is useful if we have to assume that ?i Vi
  ? o Vo given error in observations

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Mediterranean and Black Seas
Evaporative basin
Runoff/precipitation