Oceanography Section 1 Flashcards
Section 1
What are ocean currents effected by
Global winds, coriolis effect, land, gravitational pull of the moon, density differences
Why do global winds happen
Earth is unequally heated which makes high latitudes colder than low which causes the global winds cycle where wind rises and falls and spreads out
What does the Coriolis effect do
it makes wind in the north go right and in the south go left
Why do global winds effect water
When global winds hit water, air’s friction makes the water move
How many gyres are there
5 gyres (2 in atlantic, 2 in pacific, 1 in indian ocean)
What is ekman transport
When wind hits water water travels right or left depending on hemisphere and it at first goes 45 degrees but it spirals down and the water in general goes 90 degrees left or right
Why do gyres have hills in them
Ekman transport forces water inside of gyres making them have hills
What is geostrophic flow
Geostrophic flow is when the coriolis effect pushes water to the middle of the hills but gravity pulls it down and so the water moves in a circular motion in the hill
What is western intensification
The coriolis effect causes water to stack in the west of gyres, making the hill lopsided
What does western intensification do
Water on the east turn early, making the water slower and colder and wider. The west it turns as late as possible, making the water faster, warmer and thinner
Why are gyres important for the world
They transfer warm water from the equator to high latitudes and cold water from high latitudes to equator
what is an eddy (eddies)
they are circular loops of flowing water that break off their currents. They are similar to oxbow lakes in streams
Difference between clockwise and counterclockwise eddies.
clockwise is warm core and downwelling happens. Counterclockwise is cold core and upwelling happens.
What causes countercurrents
When wind is weak water piles up and gravity brings it counter to winds
what is the 3 celled model
how wind moves. First it heats up in the equator and rises and then it spreads out to 30 where it sinks and the air then goes to 60 degrees and air from 30 and 90 converge making it rise and spread out to 90 and back to 30.
