Stream-like movement of water Let’s Review! 1) Please take out your Ch14.1 2-Column Notes. 2) Spend a few minutes reading the content for review. 3) Open book to p. 416. Ocean Currents: Stream-like movement of water

Surface Currents 2facts: caused by wind Stream-like movement of water at or near the surface

Surface currents are controlled by: Four Things: 1. Global winds- winds that blow across the surface, creating ripples

Surface currents are controlled by: 2. Coriolis Effect: Earth’s rotation causes wind and currents to curve. Coriolis Effect http://www.nasa.gov/audience/forstudents/brainbites/nonflash/bb_home_corioliseffect.html

Currents and Temperature

3. Continents deflect the current, changing its direction 4. Water temperature- Cold water from poles displaces rising warm water at equator warm water from equator is pushed back to poles

?Deep Currents? Stream-like movements of ocean water far below the surface. Caused by differences in DENSITY. Density in ocean water caused by: temperature and salinity differences

More Deep Currents… 1. decreasing temps near poles-cold water is denser so sinks to bottom 2. increasing salinity thru freezing-as ice forms, salt squeezed out, increases the salinity, changing density, water will sink 3. increasing salinity thru evaporation-salt left behind, denser, will sink

Cold Water Currents Cool land near coastal areas that would otherwise be warmer

Density Serious Saltiness lab Summary: If temperature goes down, density goes ____________. If salinity goes up, density goes _________.

Upwelling Cold, nutrient-rich water from the deep ocean rises to the surface, replacing warm surface water. Caused by wind Extremely important for organisms

Currents and Temperature