Post on 02-Jan-2016
transcript
Ocean CurrentsOcean Currents
Two Types of CurrentsTwo Types of Currents
Density Driven (deep water) CurrentsDensity Driven (deep water) Currents Wind Driven (surface) CurrentsWind Driven (surface) Currents
Density Driven CurrentsDensity Driven Currents Move water vertically through the oceanMove water vertically through the ocean Density differences cause deep water Density differences cause deep water
currentscurrents Dense water sinks at the polesDense water sinks at the poles Less dense water rises Less dense water rises
at the equatorat the equator This process creates This process creates
circulation throughout circulation throughout
the oceans of the worldthe oceans of the world
Surface CurrentsSurface Currents
Winds are primary energy source for Winds are primary energy source for surface currents.surface currents. Winds blow across the ocean surfaceWinds blow across the ocean surface friction between the wind and the ocean friction between the wind and the ocean
surface drags the water alongsurface drags the water along
Which way does the water Which way does the water flow?flow?
Rotation of the earth changes path of Rotation of the earth changes path of air and water (Coriolis Effect)air and water (Coriolis Effect)
Water flows to the right (clockwise) Water flows to the right (clockwise) in Northern Hemispherein Northern Hemisphere
Northern Pacific Surface Northern Pacific Surface CurrentsCurrents
EquatorNorth Equatorial Current
Kuroshio Current
California Current
South Equatorial Current
East Australian Current
West Wind Drift
Peru Current
Global Surface CurrentsGlobal Surface Currents
Most ocean currents have a dramatic Most ocean currents have a dramatic impact on local weather and impact on local weather and continental climate patternscontinental climate patterns
Ex: Mediterranean climate zonesEx: Mediterranean climate zones
Surface Currents in the USSurface Currents in the US
San Francisco Washington,
DC
The Gulf Stream is warm and comes from the equator/ Gulf of Mexico
The California Current is cold and comes from Alaska
What is a gyre?What is a gyre?
A roughly circular pattern of ocean A roughly circular pattern of ocean surfacesurface currents currents
Caused by the Coriolis EffectCaused by the Coriolis Effect
North Pacific GyreNorth Pacific Gyre
Equator
Why are gyres/ currents Why are gyres/ currents important?important?
Warm currents move heat from the Warm currents move heat from the equator to middle and high latitudesequator to middle and high latitudes
Gyres influence air temperature, Gyres influence air temperature, weather and climate of every weather and climate of every continentcontinent