1. Oceans, Coastlines, Shores
Unit 6: Oceanography
Oceans, Coastlines, Shores

2. The Ocean Floor – Depth
The depth of the ocean varies from sea level to over 11 km (~6.8 miles).
Mariana’s Trench is in the Pacific Ocean. It is the deepest part of all the world’s oceans.

3. Mariana’s Trench Weird Organisms
creatures-of-the-mariana-trench
List the five organisms we go over: 1. 2. 3. 4. 5.

4. The Ocean Floor – Topography
Four depth zones in the Ocean.
1- Continental shelf – shallow ocean floor
2- Abyssal plain – Deep ocean floor
3- Oceanic ridge system – submarine mountain chain
4- Oceanic trenches – Deep and narrow found along subduction zones in the ocean.

5. The Ocean Floor – Topography
Continental slope and continental rise are beyond the continental shelf.
They mark the transition between the shallow shelf (continental shelf) and the deep ocean (abyssal plain).

6. Oceans – Water Salinity
Salinity – concentration of salt in water
Salinity of ocean water changes with depth.
Salinity of ocean water is relatively uniform in the well mixed surface water, but is more extreme in deeper waters.

7. Oceans- Water Temperature
Temperature of ocean water changes with depth.
Temperature around tropical surfaces are ~27˚C (81˚ F) and ~2˚C (36˚F) for deep ocean waters.

8. Oceans- Water Density
Density determines the water’s vertical position in the ocean.
Two factors affect density: Temperature & Salinity
Salty water is more dense than fresh water.
Cold water is more dense than warm water.
Ice is less dense than liquid water.

9. Oceans – Water Density There are three ocean layers:
1- Epipelagic (surface mixed zone)
Warmest from solar energy
2- Mesopelagic (transition zone)
Between warm and cold water also called the thermocline
3- Bathypelagic (Deep zone)
Around freezing

10. Water Density – Demo Which layer is more dense? Saltier layer
Rank the following from least to most dense.
Choose from the following: Warm & Salty, Cold & Salty, Warm, Cold
Answer: Warm, Cold, Warm & Salty, Cold & Salty
Saltier layer