1. The Ocean
Chapters 19-21

2. The Water Planet
The global ocean contains 97% of all of the water on Earth.
The global ocean is divided into five major oceans:
Atlantic
Pacific
Indian
Arctic
Southern Oceans

3. Pacific Ocean The Pacific Ocean is the largest ocean on Earth.
It contains more than one-half of the ocean water on Earth.
It is also the deepest ocean with an average depth of 4.3 km.

4. Oceans The next largest ocean is the Atlantic Ocean.
The third largest is the Indian Ocean. They both have an average depth of about 3.9 km.

5. Seas
Seas are smaller than oceans and may be partially surrounded by land.
Examples are
Mediterranean Sea
Arabian Sea
Caribbean Sea

6. Ocean Exploration Oceanography- the scientific study of the oceans
Some ancient civilizations studied the oceans.
Modern oceanography didn’t start until the 1850s.

7. Oceanography
Matthew F. Maury published observations of the ocean in 1855 as one of the first textbooks.
From , a team of scientists aboard the HMS Challenger took water temps at great depths, samples of ocean water, sediments, and thousands of marine organisms.

8. Modern Oceanography
JOIDES Resolution was the largest and most sophisticated scientific drilling ship in the beginning of the 21st century.
The Japanese ship CHIKYU is the most advanced now in use.

9. Sonar
A system that uses acoustic signals and returned echoes to determine the location of objects or to communicate.
Stands for Sound Navigation and Ranging
Scientists use the information to make maps and profiles of the ocean floor.

10. Submersible Underwater research vessels
Piloted by people (bathysphere)
Self-propelled (bathyscaph)
Submarine Robots

11. Submersibles Make discoveries about the ocean Take photographs
Collect mineral samples
Allow oceanographers to study for long periods of time.

12. Ocean Floor Sediments Core samples are taken of deep floor sediments
Sediments can be inorganic or organic
A lot of sediment is created originally by living organisms- biogenic
Chemical deposits that crystallize are called nodules- they are composed mainly of oxides

13. Physical Classification of Sediment
Two main types are
Muds- very fine silt and clay sized particles of rock
Ooze
Calcareous ooze is made of calcium carbonate
Siliceous ooze is made of mostly silicon dioxide which comes from the shells of radiolarians and diatoms.- Mostly in Antarctica.

14. Salinity of Ocean Water
Salinity is a measure of the amount of dissolved salts and other solids in a given liquid
Salinity is measured by the number of grams of dissolved in 1,000 g of ocean water.
Ocean is about 3.5% salts
Fresh water is less than .1%

15. Salinity The global ocean is an average of 34.7%
The Red Sea is about 40%. It is due to the hot, dry climate around the Red Sea, which causes high levels of evaporation.

16. Temperature of Ocean Water
Temp varies depending on depth and location.
The range of ocean temps depends on the amount of solar energy an area receives and by the movement of water in the ocean.

17. Color of Ocean Water
Substances or organisms in ocean water, such as phytoplankton, can effect the color of the water.
Phytoplankton reflect green light.
Studying variations in the color of the ocean, scientists can determine the health of the ocean.

18. Tides and Waves Waves have two basic parts- a crest and a trough
The wavelength is the distance between two consecutive crests.
The wave period is the time required for two consecutive wave crests to pass a given point
Speed= wavelength/ wave period

19. Wave
A wave is a disturbance that carries energy through matter or space.
A medium is the matter through which a wave travels. Air, water, etc.

20. Waves
When a wave meets a boundary, the wave bounces back. When a wave passes the edge of an object or passes through the opening, the wave bends. A wave also bends when it passes from one medium to another at an angle.

21. Parts of a Wave

22. Reflection, Diffraction, and Refraction
Reflection- is the bouncing back of a wave when it meets a surface or boundary
Diffraction- the bending of waves as they pass an edge
Refraction- the bending of waves when they pass from one medium into another. All waves are refracted at an angle.

23. Waves

24. Interference
When several waves are in the same location, they combine to produce a single, new wave that is different from the original waves.
Two types:
Constructive interference- adds the total intensity
Destructive interference-Subtracts the intensity

25. Doppler Effect
Example: You are standing outside and an ambulance passes by. The pitch of the siren goes from higher to lower. Why?
An observed change in the frequency of a wave when the source or observer is moving.

26. Ocean Currents
A horizontal movement of water in a well-defined pattern, such as a river or stream.
Surface currents
Deep currents

27. Ocean currents Factors influencing currents:
Wind-transfers kinetic energy to the water- Global wind belts effect the direction of the wind
Location of continents- Continental barriers
Coriolis effect- Earth’s rotation also effects the currents
Causes gyres or a huge circle of moving ocean water found above and below the equator

28. Major Currents Equatorial Countercurrent
Antarctic Circumpolar Current (West Wind Current)
Gulf Stream that widens into North Atlantic Current

29. Ocean Currents Regulate the climate in the areas around them
Help distribute nutrients and species around the world
Help prevent the ocean water from being stagnant

30. Behavior of Tides
Because there are two tidal bulges, most locations in the ocean have two high tides and two low tides daily
Spring Tides are when the tides are the strongest- New moon and full moon
Neap tides- first and third quarter moon/ weakest tides

31. Tidal Variations
Tidal patterns are influenced by the size, shape, depth, and location of the ocean basin in which they occur.
They are also affected by tidal oscillations.
Slow rocking motion of the ocean water that occurs as the tidal bulges move around the ocean basins.

32. Tidal Currents
When the tide flows toward the coast it is a flood tide.
When the tidal current flows toward the ocean it is called an ebb tide.
When there is no tidal current, it is called a slack current.