OCEAN CURRENTS

current mass of water moving from one place to anotherlike a river within the ocean

importance:

moves drifting organisms from place to place plankton, disperse youngcarries eggs and larvae of organisms that have external fertilizationbrings food, oxygencarries away waste,pollutants

three types of currents surface currents thermohaline circulation (currents) wind-driven vertical currents (upwelling)

surface currentswind driven currentsoccur at surfacehorizontal currentscaused by friction between wind and water - wind pushes water

surface currentsCoriolis effectcauses moving objectsin northern hemisphereto veer clockwisecauses moving objectsin southern hemisphereto move counter-clockwise

surface currentsCoriolis effect

surface currentsgyre

massive circular system of wind-driven surface currentscover whole oceansclockwise inNorthern hemispherecounter-clockwisein Southernhemisphere

surface currentseddies = warm core ringsbreak off of currents and transport organisms elsewhere

thermohaline circulation (currents)

causes deep ocean circulationvertical currentstemperature and salinity cause water density differencesdue to density differences, water masses rise and fall

thermohaline circulation (currents)

salinity = density = water mass sinks temp. = density = water mass floats

thermohaline circulation (currents)

thermohaline circulation (currents)

when combined with surface currents, results in conveyor belt movement of water around globe

wind driven vertical currents = upwellingwind blows, moves water away, causes new water to rise up to replace it

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