surface ocean currents

Question 1

ocean current

Answer 1

flow of ocean water caused by global winds, coriolis effect, land, gravitational pull from moon, density differences

Question 2

what causes seasons?

Answer 2

earths axis causes some places to be hit by the sun more directly than others

Question 3

coriolis effect

Answer 3

rotation of the earth causes winds in northern hemisphere to veer right, winds in souther hemsphere to veer left

Question 4

what is the three celled model

Answer 4

a model of the global wind currents in three cells of convection currents
polar cell (90-60), ferrel cell (60-30), hadley cell (30-0)
also forms polar easterlies, prevailing westerlies, ne trade winds, se trade winds, prevailing westerlies, and polar westerlies from coriolis effect

Question 5

what are gyres and how are they formed?

Answer 5

gyres are circular flows of water formed by interactions with the wind from the coriolis effect
there are five major gyres

Question 6

ekman transport

Answer 6

the coriolis effect also effects water, so water will also go and veer to the right/left
therefore, water goes right/left 45º compared to the wind on the surface
as you go down, the coriolis effect continues and creates a spiral as the water turns more and more but also reduces in speed
the net water transport would be 90º to the direction of wind in ideal conditions

Question 7

what are hills in gyres?

Answer 7

ekman transport pushes surface water towards the center of the gyre since the wind moves outwards, creating a sort of hill of water
the surface water is pulled downhill outwards by gravity but pulled inwards by the coriolis effect, creating circular geostrophic flow that gives gyres their circular shape

Question 8

what are western boundary currents and how are they caused?

Answer 8

the spinning of earth moves the hills of gyres towards the west
this makes the currents on the west side of gyres (western boundary currents) stronger than the ones on the east (eastern boundary currents)

Question 9

eddies

Answer 9

flow of water can meander and form eddies similar to oxbow lakes
they are circular rings of flowing water that flow in the opposite direction of the main current next to them

Question 10

cold-core rings

Answer 10

cold-core rings flow counter(north) or clock(south) and keep cold water inside them
due to the coriolis effect, their net water transport is outwards so it pushes away warm surface water and allows cooler deep water to rise
since it spirals outwards and sucks water up, this is called up welling

Question 11

warm-core rings

Answer 11

warm-core rings flow clock(north) or counter(south) and keep warm water inside them
due to the coriolis effect, their net water transport is inwards so it keeps warm surface water inside it
since it spirals inwards it pushes water down, this is called down welling

Question 12

countercurrents

Answer 12

currents not formed by wind in areas with weaker winds
flow counter to the wind flow in hemisphere and form around equator
form from gravity due to the west-skewed hills of gyres