Physical Oceanography

1. Physical Oceanography The Oceans Sea Water Ocean Movements Chap. 15

2. Objectives The Oceans – 15.1 • identify methods used by scientists to study Earth’s oceans • discuss the origin and composition of the oceans. • describe the distribution of oceans and major seas

3. Introduction

4. Introduction • Uses What are some useful features of oceans?

5. Introduction • Uses • travel • fishing/food • recreation

6. Introduction • Uses • Studying

7. Introduction • Uses • Studying • H.M.S. Challenger Measured depth, water temperature, fauna, current, and other data. First measured Mariana trench (26,890 ft.)

8. Introduction • Uses • Studying • H.M.S. Challenger • Meteor Used sonar to map undersea topography

9. Example Calculation A sonar signal travels about 1500 m/s in ocean water. If it takes 6 seconds for a signal to return to the ship after it is emitted what is the distance to the ocean floor?

10. Introduction • Uses • Studying • H.M.S. Challenger • Meteor • TOPEX-Poseidon NASA satellite that measures ocean data

11. TOPEX/Poseidon • tracks ocean tides • measures sea levels (to 5 cm accuracy) • monitors climates by measuring ocean temperatures.

12. Ocean origins

13. Ocean origins • Oceans are as old as Earth’s rocks

14. Ocean origins • Oceans are as old as Earth’s rocks • Lava flows have been dated at 4.6 b.y.

15. Ocean origins • Oceans are as old as Earth’s rocks • Lava flows have been dated at 4.6 b.y. • These formed rocks by cooling quickly (in water)

16. Ocean origins • Oceans are as old as Earth’s rocks • Source of water

17. Ocean origins • Oceans are as old as Earth’s rocks • Source of water • Comets (dirty snow balls)

18. Ocean origins • Oceans are as old as Earth’s rocks • Source of water • Comets (dirty snow balls) • Water was trapped in Earth when it formed. Volcanoes released this into the atmosphere.

19. Earth’s Water This is also called the hydrosphere

20. Earth’s Water • Location Where is the Earth’s water found?

21. The Hydrosphere

22. The Hydrosphere

23. The Hydrosphere

24. The Hydrosphere

25. The Hydrosphere

26. The Hydrosphere

27. Earth’s Water • Location • Amount of frozen water has varied

28. Earth’s Water • Location • Amount of frozen water has varied • During ice ages as much as 10% of hydrosphere was frozen.

29. Earth’s Water • Location • Amount of frozen water has varied • During ice ages as much as 10% of hydrosphere was frozen. • Sea level varied by hundreds of meters. Due to melting of glaciers and tectonic forces altering sea floor.

30. Earth’s Water • Most of Earth’s surface is covered by water (71%)

31. Earth’s Water • Most of Earth’s surface is covered by water (71%) • The hemisphere contains higher percentage of water.

32. Earth’s Water • Most of Earth’s surface is covered by water (71%) • The southern hemisphere contains higher percentage of water. • All oceans are connected.

33. Earth’s Water • Most of Earth’s surface is covered by water (71%) • The southern hemisphere contains higher percentage of water. • All oceans are connected. • Pacific, Atlantic, and Indian oceans are main oceans.

34. Earth’s Water • Most of Earth’s surface is covered by water (71%) • The southern hemisphere contains higher percentage of water. • All oceans are connected. • Pacific, Atlantic, and Indian oceans are main oceans. • Seas are partly or mostly surrounded by land.

35. Earth’s Water • Most of Earth’s surface is covered by water (71%) • The southern hemisphere contains higher percentage of water. • All oceans are connected. • Pacific, Atlantic, and Indian oceans are main oceans. • Seas are partly or mostly surrounded by land. • Sea ice forms in the Arctic and Antarctic seas.

36. The End

37. Objectives Seawater - 15.2 • compare & contrast physical and chemical properties of seawater • explain ocean layering • describe the formation of deep-water masses

38. Chemical Properties

39. Chemical Properties • Salinity A measure of the dissolved salts in water.

40. Chemical Properties • Salinity • Sea water is about 35 parts per thousand (ppt) salts

41. Chemical Properties • Salinity • Sea water is about 35 parts per thousand (ppt) salts • Salts include Na+, Cl- , SO42-, Mg2+, Ca2+, K+, HCO3-, and others

42. Chemical Properties • Salinity • The salinity varies and is lower where there is . . .

43. Chemical Properties • Salinity • The salinity varies and is lower where there is . . . • a lot of precipitation

44. Chemical Properties • Salinity • The salinity varies and is lower where there is . . . • a lot of precipitation • an estuary/river delta

45. Chemical Properties • Salinity • The salinity varies and is lower where there is . . . • a lot of precipitation • an estuary/river delta • melting of glaciers

46. Chemical Properties • Salinity • Source of sea salt

47. Chemical Properties • Salinity • Source of sea salt • the atmosphere (Cl- and SO42-)

48. Chemical Properties • Salinity • Source of sea salt • the atmosphere (Cl- and SO42-) • weathering rocks (Na+, K+, Ca2+ from feldspar)

49. Chemical Properties • Salinity • Source of sea salt • Removing sea salt

50. Chemical Properties • Salinity • Source of sea salt • Removing sea salt • deposited when water evaporates