1. Ocean Water Chemistry

3. Figure 4.17a

5. http://www.nhptv.org/

6. Distribution of Earth’s Water Oceans97.2 % Ice Caps and Glaciers2.15 % Atmosphere0.001 % Rivers and Lakes0.009 % Inland Seas 0.008 % Groundwater0.625 %

7. Ocean Water is SALTY Salinity: Total amount of dissolved solids Units: o / oo = 1/1000 Range: 33 – 37 o / oo Increase in salinity: –Increase in Density –Decrease in Freezing Point –Decrease in Vapor Pressure –Increase in Osmotic Pressure

8. Origin of Salts in Oceans Rivers (largest transport of chemicals to ocean) –Rain + CO 2  H 2 CO 3 –Si, Al, Na, K, Mg Volcanoes –Cl, S, CO 2 Dust / Rain –Fe, Si Anthropogenic –CO 2, P

9. Example Geochemical Cycle Concept of Steady State

10. Example 2 Geochemical Cycle

11. Residence Time (T = Ocean amount/Output rate) Concentration of elements in seawater is determined by their removal rate Conservative elements: –Major Elements: Cl, Na, SO 4, Mg, Ca, K -Minor Elements: Br, Sr, B, C, F Non Conservative Elements –Nutrients: N, P, Si –Dissolved gases: O 2, CO 2, N 2 –Trace Elements: Fe, Al, Mn –Organic Compounds

12. Residence Time - Concentration ElementRes. Time (yrs ) Na60 000 000 Cl80 000 000 Mg10 000 000 K6 000 000 SO 4 9 000 000 Ca1 000 000 Mn7 000 Fe100 Concentration Crust (%)Ocean (mg/l) 2.410 770 0.01319 500 2.31 290 2.1380 0.026905 4.1412 0.50.0002 2.40.002

14. Dissolved Gases Gas Solubility: Decreases with Temp. and Salinity Increases with Pressure

15. Gases in Atmosphere & Oceans Percent Gas Phase by Volume GasAtmosphereSurface OceanTotal Ocean N2N2 79%48%11% O2O2 21%36%6% CO 2 0.04%15%83%

17. Seawater pH Pure water pH = 7 Seawater pH = 7.5 – 8.1 Seawater is very well buffered! CO 2(gas) +H 2 O  H 2 CO 3  H + +HCO 3  2H + +CO 3 2

21. H 2 O: Universal Polar Solvent

22. H 2 0: Temperature and Density

23. H 2 O: Frozen & Liquid density

24. H2O: Heat Capacity Heat Capacity: heat needed to change the temperature of a substance Water has higher heat capacity than: –All solids –All liquids, except liquid ammonia Latent heat of Vaporization: heat needed to evaporate a liquid –Water has the highest of all substances

25. Seawater: Temperature and Density

26. Seawater: Temperature and salinity

27. Seawater: Ice Formation

29. Electromagnetic wave penetration

30. Open water (low productivity)

31. Coastal and Estuarine waters (high productivity)

33. Nuclear Missile Submarine

36. http://www.nhptv.org/

37. How do we measure light penetration? Secchi Disc

38. Water Refraction Eschrichtius robustus

39. Sound Velocity Influenced by Salinity, Temperature and Pressure –Increases with Salinity –Increases with Temperature –Increases with Pressure Concept of Midwater Sound Channel Study in Detail Fig 5-19!

40. Sound Channel

42. Humpback Whales Megaptera novaeangliae

43. Gray Whale & Sonar Proposal Eschrichtius robustus

44. Gray Whale Migration

45. Acoustic Pollution