1. Oceanography

2. Exploring the Ocean Floor
Continental Shelf: gradually sloping end of a continent that extends out under the ocean
Continental Slope: true edge of a continent; steeper than shelf
Abyssal Plain: smooth, nearly flat deep region of the ocean floor
Trench: steep canyon in the ocean floor; so deep, cannot see the bottom

3. Exploring the Ocean Floor
Seamount: completely underwater volcanoes
Guyot: seamounts with flat, eroded tops
Volcanic Islands: underwater volcanic mountains whose peaks break the surface of the ocean
Mid-Ocean Ridge: continuous range of mountains with cracks for magma to flow

4. Ocean Composition The ocean is salty! (31% sodium and 55% chlorine)
Oceans are 96.5% water and 3.5% dissolved salts
WHY?
Rivers and streams deposit minerals into the ocean
When water evaporates, the salt is left behind
Salinity: the measure of how much salt is in the water

5. The Dead Sea

6. Waves
Waves: the movement of energy through a body of water

7. Waves
Wind blows across the surface and gives its energy to the water creating waves (the energy is moving, NOT the water)
The size of the wave depends on the strength of the wind and on the length of time it blows
Can be CONstructive and DEstructive

8. Waves
Wavelength – distance from one crest to the next consecutive crest
Wave height – the distance from the crest of a wave to the next consecutive trough
Frequency (or period) – the number of waves that pass through a point in a given amount of time

11. Special Waves
Breakers - As the wave moves into increasingly shallow water, the bottom of the wave decreases speed. There comes a point where the top of the wave overtakes it and starts to spill forward — the wave starts to break.
Tsunamis – giant waves that form due to volcanoes or earthquakes that occur on the ocean floor

12. Tides
Tides: the daily rise and fall of Earth’s waters on its coastlines
caused by the gravitational pull of moon and the Sun
the moon’s effect is about twice as much as the Sun’s because it is closer to the Earth
Tidal range: difference between high and low tide

13. Tides The moon pulls on the Earth and the ocean
The pull is strongest on the part of the Earth directly facing the moon (A) causing a bulge or a high tide
As the ocean (A) and the Earth (B) are pulled, a bulge or high tide is left on the other side of the Earth (C)
These bulges (A & C) cause the water level in the places between them (D & E) to decrease. causing low tides
Most shores have 4 tides a day, 2 high and 2 low D E

14. Tides Location of the Sun may impact tides
Spring Tides: huge difference in high and low tides; high tides are really high and low tides are really low
Neap Tides: small difference in high and low tides; high tides are not that high and low tides are not that low

15. Currents
Currents: large streams of moving water that flow through the oceans
Carry water great distances unlike waves
Surface Currents

16. Currents Surface Currents: currents that occur at or near the surface
Caused by winds pushing water across the ocean
Follow wind patterns and move in circular patterns
Why circular?
Currents meet continents and change direction (deflect)
Earth is spinning so wind can’t blow straight: Coriolis Effect
Greatly affect climate; warm water moves from the equator and cool water moves from polar regions
Warm and cool currents warm or cool the air above

17. Coriolis Effect http://noaacontent.nroc.org/lesson08/l8ex1.htm

18. Currents
Deep Ocean Currents: currents that carry colder, denser water along the ocean floor from the poles to the equator
caused by differences in density
Density of water depends on temperature and salinity
Move and mix all over Earth

19. Resources https://www.youtube.com/watch?v=12V3u7bSTlI (Kenya)
(upwelling)
(Uganda)
(mitigation)