OCEAN, ATMOSPHERE, AND CLIMATE – CLASS NOTES
Prof. Neil Blair – n-blair@northwestern.edu – Office Hours by appt.
09/21/21
 Weekly, find news article about ocean or atmosphere, must be based on
scientific study
09/23/21

Explire OAC canvas, missed posted lecture
09/30/21
 Navigation
o Latitude lines run E-W, Longitude N-S
 Lat determined by north star (northern hemisphere),
horizon is 0 degrees, wherever the star sits from there is
the degree of latitude. Northpole is 90 degrees, equator is
0 degrees
 Sextant measures lat, aligns horizon with north star.
 Lon. Origionaly determined by “running the latitude”, go
down to the Lat of target, go in that direction.
 Determine noon based on when smallest shadow of mast
is, set as noon, see when noon changes
 Earth rotates 360 degrees in 24, 15 egrees per hour. One
hour means 15 degrees of longitude. Determine E/W by if
you gained or lost time.
o LOng Range Navigation, terrestrial radio stations. Able to
triangulate location when not too far to shore.
o Global Positioning System
 Reliant on satellites. Receiver, pick up at least three and
triangulate location.
 Each satellite has a different signal, gps uses delay in signal
to determine relative distance to satellite.

10/07/21
 Thermohaline Circulation
o Temp + Salt = change in density of water
 Wind Circulation
o Due to friction, causes waves
 Waves vs Currents
o Energy movement vs mass movement
 Doppler effect
o As noise source approaches, velocity is added to sound waves
hence increase in pitch on approach, and reciprocal effect.
 Ocean water is ~96% H20, ~4% salt.
 Base of ocean uniform temp due to dense water and thermohaline
circulations, 4-5 degrees centigrade
 Global warming, causes ice to melt. Low density fresh water has the
capability to throw off the thermohaline circulation, and cease the
refrigeration effect of deep ocean currents.
 Coriolis Effect
o Different places on earth are rotating at different velocities,
quito vs buffalo. A projectile sent from quito inherits its higher
velocity, opposite is true for buffalo.
o Impact of the spinning on the east west parts of trajectories.
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o Winds inherit these velocities as well, they seem to “curve” to
the right in the northern hemisphere, and to the left in the
southern hemisphere.
o Basically tugging everything to the right in northern, tugging to
the left in southern.
 Ekman Spiral
o Due to wind, lower currents move at right angles to the wind.
o Water moving away from the current upwells cold water
 Use APA Citations
LAB 2
 Atmospheric cells chart
o Hadley Cell
 Near equator, air moves towards equator rises cools,
moves towards poles
 Rain
 0 degrees
o Ferrel Cell
 Cold air sinks and moves when warmed along the ground
towards the poles (counter Hadley Cell)
 No precipitation
 30 degrees
o Polar Cell
 Warm air rises, cools, snows/clouds, cool air moves
towards the poles
 Rain/Snow
 60 degrees
 Most rain on the planet occurs at the equator
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