What percent of the earth is covered in water or land?

What percent of the earth’s water is salty or fresh?

Ocean Salinity

World Ocean Facts – which ocean is the biggest? Area (1,000,000 km²) Volume (1,000,000 km³) Average Depth (m) Maximum Depth (m) Atlantic Ocean Pacific Ocean ,022 Indian Ocean Arctic Ocean

HW: What makes the ocean salty? Think about why the highest salinity is found near equator.

Lab Inquiry: How does temperature and salinity affect the density of ocean water?

Oceanic Circulation Aim: Why causes the currents in the ocean?

Vocabulary Salinity Density Upwelling Gyre Currents Thermal Expansion Coriolis Global Winds

Why is Ocean Circulation Important? a. Transport ~ 20% of latitudinal heat between Equator and poles b. Transport nutrients and organisms c. Influences weather and climate d. Influences commerce e. Pollution is transported

2 kinds of circulation: a.Surface driven currents are wind-driven and occur in the uppermost 100 m or less of ocean b.Deep ocean currents are caused by density changes due to salinity and temperature differences. These currents produce very slow flows in deeper waters. c.Other forces affecting currents: Coriolis effect, friction, gravity, thermal expansion, geologic shape of ocean basin and landmasses

How fast? A few miles/hr (Gulf Stream off of Miami = 4.5 mph) How much? Total water in ocean surface circulation = about 100 Amazon Rivers (20 million m 3 /s).

N. Atlantic Gyre S. Atlantic Gyre N. Pacific Gyre S. Pacific Gyre Indian Ocean Gyre Antarctic Circumpolar Current

Gyres are large circular-moving loops of water Five main gyres (one in each ocean basin): North Pacific South Pacific North Atlantic South Atlantic Indian Generally 4 currents in each gyre Centered about 30 o north or south latitude Current Gyres

ESRT Surface Ocean Currents pg. 4 Color the war currents red and the cool currents blue COqYI&feature=player_embedded

Surface Currents are created by: 1. Global Winds 2. Coriolis Effect 3. Solar Heating (temperature, density)

Global Winds pg. 14 ESRT Surface currents of ocean generally mirror atmospheric circulation (wind) patterns

equator Quito Buffalo 79 o W North Pole South Pole N Quito Buffalo equator Buffalo moves 783 mph Quito moves 1036 mph 15 o

The Coriolis effect on Earth As Earth rotates, different latitudes travel at different speeds The change in speed with latitude causes the Coriolis effect

Coriolis Effect a.The rotation of Earth causes a deflection (curve) of the winds and waters of the Earth. In Northern Hemisphere, curvature is to right - clockwise In Southern Hemisphere, curvature is to left – counterclockwise b. Effect lessens at equator and increases at poles Visualization of the Coriolis effect: th_science/terc/content/visualizatio ns/es1904/es1904page01.cfm?chapt er_no=visualizationhttp:// th_science/terc/content/visualizatio ns/es1904/es1904page01.cfm?chapt er_no=visualization Wind: cience/terc/content/visualizations/es1905/ es1905page01.cfm?chapter_no=visualiza tionhttp:// cience/terc/content/visualizations/es1905/ es1905page01.cfm?chapter_no=visualiza tion

A)Idealized winds generated by air pressure differences and Coriolis Force. B)Actual wind patterns affected by land mass distribution..

Ocean Circulation & Global Winds

Sea Surface Temperature

Thermal expansion Solar radiation heats the water at equator more than the poles Warm water expands and cool water contracts, creating a water bulge at the equator Gravity pulls warmer water “downhill” toward cooler water

Ocean Salinity Increased evaporation near the equator makes the water saltier.

Global ocean circulation that is driven by differences in the density of the sea water which is controlled by temperature and salinity.

Thermohaline Circulation - The Ocean Conveyor

Equatorial to polar heat transport and water flow

LINKS: com/watch?v=w_8m w-1HYFghttp:// com/watch?v=w_8m w-1HYFg com/watch?v=nAq9 LXLXISkhttp:// com/watch?v=nAq9 LXLXISk com/watch?v=rR5TF WNLtOc&feature=rel atedhttp:// com/watch?v=rR5TF WNLtOc&feature=rel ated com/watch?v=boiFo SRq1BM&feature=re latedhttp:// com/watch?v=boiFo SRq1BM&feature=re lated

What do Nike shoes, rubber ducks, and hockey gloves have to do with currents?

Lost at Sea

Barber’s Point

“Great Pacific Garbage Patch” Estimate: 46,000 pieces of floating garbage/mi 2. North Pacific Subtropical Gyre

135° to 155°W and 35° to 42°N

North Pacific Subtropical Gyre Great Pacific Garbage Patch- Good Morning America