1. Oceans

2. Name the oceans

3. Just joking. There is only one ocean.
Name the oceans
Just joking. There is only one ocean.

4. Name the parts of the ocean
North Atlantic
South Atlantic
North Pacific
South Pacific
Indian
Antarctic
Arctic?

5. Name the parts of the ocean
North Atlantic
South Atlantic
North Pacific
South Pacific
Indian
Antarctic
Arctic?

6. Name the parts of the ocean
Arctic?
North Pacific
North Atlantic
Antarctic
South Atlantic
Indian
South Pacific

7. Name the parts of the ocean

8. Statistics Area—~ 340 million km2 (71% of surface) Average Depth—3800m
Salinity—35g salt/kg of ocean water (varies)
Average Temperature--Surface: 17oC (63oF)
Deep: 3oC (37oF)

9. Temperature
Where would you find warmer surface water?

10. Temperature Where would you find warmer surface water? Cooler Warmer

11. Temperature Surface water is warmer than deep water
From 200 m to 1000 m deep, temperature drops sharply.
This region is called the thermocline

13. Density Surface water is less dense than deeper water
From 100 m to 1200 m, the density rises sharply
This region is called the pycnocline

15. What causes density differences?

16. What causes density differences?
Temperature and salinity

17. What causes density differences?
Temperature and salinity
Cooler water is more dense
Saltier water is more dense

18. Where will you find the saltiest surface water?

19. Where will you find the saltiest surface water?
Surface water in the tropics.
Evaporation is the highest there.
…but it’s warm water
Surface water near the poles.
Freezing sea water freezes the water and leaves the salt.

20. Why does ocean water move?

21. Why does ocean water move?
Wind
Density differences
Coriolis effect

22. Why does ocean water move?
Wind—surface water moves in the direction of the wind
Density differences
Coriolis effect

23. Why does ocean water move?
Wind—surface water moves in the direction of the wind
Density differences—more dense water sinks under less dense water
Coriolis effect

24. Why does ocean water move?
Wind—surface water moves in the direction of the wind
Density differences—more dense water sinks under less dense water
Coriolis effect—water flowing north or south bends to the right in the northern hemisphere.

25. Why does deep ocean water move?

26. Why does deep ocean water move?
Density differences, mainly.
Masses of water sink near the poles, traveling thousands of kilometers before mixing with other layers
The tides also affect deep water.

27. The thermohaline current (deep)

28. Surface currents

29. Currents have to turn when they hit a continent
Surface currents
Currents have to turn when they hit a continent

30. Surface currents
Cold currents come from polar waters

31. Surface currents
Warm currents come from equatorial waters

32. Surface currents
Currents heading towards the poles bend east

33. Surface currents
Currents heading away from the poles bend west

34. Currents circle clockwise in the northern hemisphere
Surface currents
Currents circle clockwise in the northern hemisphere

35. Currents circle counterclockwise in the southern hemisphere
Surface currents
Currents circle counterclockwise in the southern hemisphere

36. Warm currents include:

37. Warm currents include:
The Gulf Stream, Alaska, Brazil and East Australia Currents

38. Cold currents include:

39. Cold currents include:
The California, Peru, Canary and West Australia Currents

41. Ekman Drift Winds blow east or west in bands by latitude
(PS: winds are named by where they come from)

42. Ekman Drift
The water below the surface pulls to the right in the northern hemisphere

43. Ekman Drift
Ekman drift causes a mound of water to pile up between the bands of wind.

44. Geostrophic Currents
Coriolis forces and Ekman drift force water to move in a circle
These currents are called geostrophic currents

45. Why does ocean water move?
Wind
Density differences
Geostrophic forces
Tides

46. Gyres The circular pattern formed is called a gyre.
There are about 5 major gyres, and 10 minor ones

47. Gyres
Gyres carry heat around.
Trash collects in the center of a gyre

48. Gyres The speed of the water depends on the width of the current
It takes several years for water (and floating objects) to be carried around a gyre.
Gyres

49. Upwelling and downwelling
Ekman drift near a continent can move water away from shore. Water comes up from below to replace it.

50. Upwelling and downwelling
Ekman drift near a continent can move water away from shore. Water comes up from below to replace it.
Reverse the wind, or place the continent on the other side to force downwelling

51. El Niño

52. El Niño
…upwelling at the west coast of South America decreases…

53. El Niño …upwelling at the west coast of South America decreases…
…leading to warmer surface waters…

54. El Niño …upwelling at the west coast of South America decreases…
…leading to warmer surface waters…
…reversing the prevailing winds…

55. El Niño …upwelling at the west coast of South America decreases…
…leading to warmer surface waters…
…reversing the prevailing winds…
…changing rainfall and temperature patterns over the entire western hemisphere.

56. Walker Circulation
Normal wind pattern

57. Walker Circulation
El Niño events reverse the wind pattern

58. Weather vs. Climate

59. Weather vs. Climate
Short term
Long term

60. Weather vs. Climate Short term Hourly Daily Weekly Yearly Long term
Over many years—using historical or geologic data

61. Weather vs. Climate Both include: Total precipitation
Type of precipitation
Temperatures
Wind patterns
Seasonal variations in all of the above

62. Teleconnections
--when the cause is far removed from the effects

63. Teleconnections --when the cause is far removed from the effects
With weather patterns:
-the position of the jet streams
-moisture content of air masses and
-temperature of air masses
can cause effects far away

64. Temperature anomalies

65. Rainfall anomalies