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The Oceans

Oceans• Ocean water is a mixture of salts and gases.• Salinity is the proportion of dissolved alts

in water.• Continental shelf is a gentle sloping plain

of shallow water forming along the coasts of the continents.

• Past the shelf is a continual slope.• Trenches cut through the shelf and slope.

Oceans

• Light and Temperature decrease the deeper you go

• Pressure increases as you go deeper. Deep ocean is about 50x greater than the atmosphere

Currents• surface currents – a large stream of water

moving in the same direction, caused by wind blowing across the ocean surface.

• Generally the follow wind patterns – warm water moves away from equator and vice versa

• Deep currents – caused be difference in the density of ocean water

• Upwelling – winds blow warm surface water aside allowing cold water to replace it

Wave erosion and Deposition

• Hydraulic action occurs when waves pound cracks in rocks.

• Abrasion occurs when sediment carried by waves acts like sandpaper to erode rocks.

• Longshore drift moves sand along a shore.

• Depositing this sediment creates beaches.• Show waves crashing video