Lecture 8 Notes: Ocean Dynamics
Though the title of the course is Acoustical Oceanography, weve spent precious little
time on the ocean per-se (for good reasons, but ). So in this lecture well try to correct that.
The first part of the lecture is a quick
Lecture 10: Tides
What are tides?
Periodic, short-term changes in the height of the ocean
surface at a particular place.
Longest oceanic wave.
Generated by gravity and inertia between the Earth, Moon, &
Two tide producing forces:
o The EARTH-
Lecture 13: Phytoplankton & Primary Production
Drift in the ocean currents (cant swim)
Most biomas on earth consists of plankton.
Phytoplankton (plant) Autotrophic.
Zooplankton (animal)- Heterotrophic.
LECTURE 7: SURFACE CURRENTS
Coriolis Effect: Causes deflection in the path of a moving
body across earths surface.
Basically the deflection of any object that moves across
latitude of the earths surface.
The reason this occurs is be
Lecture 9: Waves
What are waves?
Ocean waves move energy across the sea surface.
Energy is moving at the speed of the wave.
The water is not moving at the speed of the wave.
Crest highest part of the wave above average water leve
Lecture 12: Gulf of Mexico
Gulf of Mexico Sea Floor:
Shallow & Intertidal areas (<20 m deep)=38%
Continental Shelf (20-180 m)=22%
Continental Slope (>3,000 m)=20%
Formation (when did the Gulf of Mexico Form)?
Little is known prior to the late Triassi
Lecture 8: Thermohaline Circulation
Where Does Deep Water Form?
Deep-water forms where air temperatures are COLD and
where salinity of surface waters are relatively HIGH.
Deep Ocean Currents:
o Are below the pycnocline, affects 90% of the oceans
Lecture 4 Notes: COA Treatment
Ultimately, one wants to describe acoustic propagation through a realistic ocean/seabed
waveguide, and the simple models discussed, even with perturbations, wont suffice. At that
point, one turns to numerical methods. Luckil
Lecture 1 Notes: Electromagnetic Interpretation
There are two pictures of the acoustic field that have very clear physical interpretation: rays and normal
modes. The ray is perhaps the simplest to interpret, as the dominant paths the energy takes. The mod
Lecture 6 Notes: Finite Additions
This lecture is a bit of a potpourri of topics, but reasonably important ones, especially
given our brief format.
The first topic is a rehash of rays as interfering modes (from section 3.4.2 KPL),
which is just the Tindle
Lecture 2 Notes: Cylindrical Coordinates
In section 5.5.2 (heralded by Fig 5.18), Frisk heads for the continuous modes of the
Pekeris waveguide. The form for p(r,z) is shown explicitly as an integral in Eq. (5.175). At this
point, we will leave Frisk and
Lecture 3 Notes: Seamounts and Canyons
A ray is not a mode, and a mode is not a ray; but the two are hooked together, in a
very clever way. OK, really bad verse, but the message is correct!
To link high frequency rays with low frequency modes, a pretty ob
Lecture 5 Notes: Square Root Operations
When my two daughters were younger, I tutored them in chemistry, which they cordially
hated (at first). Invariably during a session, I would hear the phrase dont tell me what it means,
just show me how to get the an
Lecture 7 Notes: Sound Propagation
Underwater sound propagation occurs in a medium with inherently rough boundaries, as
any seagoing oceanographer can attest. Yet all too often students work on projects which have
strong scattering components, but have ne
Lecture 10 Notes: EOF Modes
So far in this course, we have concentrated on the forward problem, i.e., given an
acoustic environment (the ocean and seabed) and some physics/wave theory (the wave equation
in its various forms and approximations), we calcula
Lecture 9 Notes: Hydrothermal Venting
Lecture 14 deals with acoustical measurement techniques. As with all technology, things
change quickly some technologies endure and get expanded on (e.g., telephones, TV) and some
get superseded and fade away (e.g. ho
Lecture 11: Estuaries
What are Estuaries:
They are partially enclosed coastal bodies of water where
freshwater and salt water mix.
pH temperature and salinity varies.
Commonly found at river mouths
o Also bays, inlets, sounds, and gulfs.
Origin of Es