1. Ch. 15

2. Ocean water is a mixture of gases and solids dissolved in water 96% PURE WATER 4% dissolved elements: Cl, Na, Mg S, Ca, K

3. Salinity total amount of solid material dissolved in water. number of grams of dissolved salts in 1 kilogram of water

4. What two substances are the most abundant in Ocean Water? Sodium Chloride

5. Salts and other materials in ocean water come from: Volcanic activity in oceans Erosion of land areas by rivers Wave action along the shoreline

6. Salinity  Processes Affecting Salinity Processes that decrease salinity: Processes that increase salinity: - Precipitation - Runoff from land - Icebergs melting - Sea ice melting - Evaporation - Formation of sea ice

7. Natural Processes Affecting Salinity

8. Salinity with depth:

9. Temperature of Ocean Water Ocean water has ability to absorb sunlight which heats the water

10. Surface zone (mixed layer): Water temp higher at surface because of direct sunlight Waves and currents mix surface water and transfers heat downwards Extends 100-400 meters Warmer at equator than at poles Only place where enough light is present to grow marine plants

11. Density of Ocean Water: Density is the mass of a substance per unit volume

12. Two factors affect density 1. Salinity - Dissolved solids make ocean water more dense than fresh water 2. Temperature - Cold water is more dense than warm water

13. Most abundant gases dissolved in ocean water: Nitrogen (N 2 ) Carbon Dioxide (CO 2 ) Oxygen (O 2 )

14. Gases in ocean water (cont.) CO 2 dissolves most easily Cold water holds more dissolved gases Warm water holds less dissolved gases Think of a pot of water on the stove – what is coming out as the temperature rises??? GASES! (oxygen) The warmer the water, the less gas it holds!

15. The dissolved gases are recycled back into the air The dissolved solids do not leave, they are used by living things in the sea.

16. What’s current with the ocean? Catch my drift?

17. Currents move water from place to place

18. There are 2 kinds of currents…

19. First kind of current: 1.Surface currents : move on or near surface of ocean Friction between wind blown air and the water surface causes the water to move Controlled by wind belts, earth’s rotational effect and location of continents

20. What direction do most currents NORTH of the equator move?

21. CLOCKWISE!

22. What direction do most currents SOUTH of the equator move?

23. COUNTERCLOCKWISE!

24. Western side of ocean has warm currents traveling from equator Eastern side of ocean has cool currents moving toward equator

25. Examples of warm water currents: Gulf Stream Brazil Examples of cold water currents: California current Canary current

26. Upwelling the rise of cold water from deeper layers to replace warmer surface water. brings greater concentrations of dissolved nutrients, such as nitrates and phosphates, to the ocean surface.

28. Second kind of current: 2. Deep density currents : cold, dense currents that flow very slowly beneath surface of ocean occurs when denser seawater moves towards an area of less dense seawater

29. In the deep ocean, denser water around the Poles sinks and travels along the ocean floor toward the equator. At the same time, less dense water at the equator rises and moves towards the poles along the surface. These two events form a continuous cycle that circulate ocean water.

30. Waves Kelly Slater

31. Wave Generating forces WIND TIDES Sometimes Earthquakes

32. The Ocean Floor

33. The Topography of the Ocean

34.  Bathymetry is the measurement of ocean depths and the charting of the shape or topography of the ocean floor.  Today’s technology allows scientists to study the ocean floor in a more efficient and precise manner than ever before.

35. Sonar an acronym for sound navigation and ranging. It is also referred to as echo sounding works by transmitting sound waves toward the ocean bottom

36. Satellites able to measure small differences by bouncing microwaves off the ocean surface differences in the height of the ocean surface are caused by ocean-floor features

37. Submersibles are small underwater crafts used for deep-sea research Today, many submersibles are unmanned and operated remotely by computers. These remotely operated vehicles (ROVs) can remain underwater for long periods

38. The ocean and our land What does the ocean do to the coastline?

39. Wind Deposition when the wind stops, it drops its load

40. Dunes : mounds of wind blown sand form where soil is dry and unprotected and the wind is strong

41. Shoreline erosion is caused by: 1.waves weathering rock 2. chemical weathering 3. storms

42. Processes that Affect Coastlines 1.long term rising and falling of the sea level 2.long term uplifting or sinking of land that borders water 3.wave erosion and deposition The sea level is now rising at a average rate of about 1mm/yr

44. SUBMERGENT COASTLINES estuary : bay where freshwater and saltwater mix forms when sea level rises and sinks

47. EMERGENT COASTLINES barrier islands : long, narrow offshore ridges of sand many over 100 km long lie parallel to the shore about 3 km to 30 km offshore

48. sometimes a hazardous place to live because it is severely eroded by storms

49. Barrier Islands

50.  Protective Structures Groins, breakwaters, and seawalls are some structures built to protect a coast from erosion or to prevent the movement of sand along a beach.  Beach Nourishment Beach nourishment is the addition of large quantities of sand to the beach system. Stabilizing the Shore

51. Miami Beach Before and After Beach Nourishment

52. PRESERVING THE COASTLINE (two things that damage the coastline) 1. recreation, commercial fishing, shipping, industrial and residential development 2. pollution