OCE test 2-2

Card Set Information

OCE test 2-2
2011-03-07 19:26:56

Lecture 5
Show Answers:

  1. Cohesion
    sticks to other water molecules
  2. Adhesion
    Sticks to other types of molecules
  3. Why is the ocean blue?
    absorbs red light, reflects blue light.
  4. Main properties of water:
    • Unusual thermal properties
    • Unusual density
    • high solubility of chemical compounds in water
  5. Water vapor
    independent molecules
  6. Unusual thermal properties of water:
    • High freezing point
    • high boiling point
    • high heat capacity
    • high latent heat
  7. High heat capacity of water:
    • *capacity for a compound to absorb and hold heat
    • highest heat capacity on earth
    • ammonia higher... but...
  8. High latent heat of water:
    *probably why we have thunderstorms in florida
  9. Global thermostatic effects:
    • moderates temp. of Earth's surface.
    • ex. Equatorial oceans(hot) don't boil.
    • ex. Polar oceans(cold) don't freeze solid.
  10. Marine effect:
    Oceans moderate temp. changes day/night;
  11. Density of ice is less than density of water (T/F)
  12. Density of water decreases as temp. decreases in which threshold?
    From 4C to 0C.
  13. Density of water increases as temp. decreases down to 4C (T/F)?
  14. Dissolved solids reduce the freezing pt of water (T/F)?
  15. Salinity
    • total amount of INORGANIC solid material dissolved
    • in water (g/kg)
  16. Typical salinity
    • 3.5% or 35o/oo
    • o/oo or parts per thousand (ppt) = grams of salt per kilogram of water
    • (g/Kg )
  17. Brackish (hyposaline)
    < 33 ppt
  18. Hypersaline
    > 38 ppt
  19. What is the most abundant chemical in seawater (besides water)?
  20. Adding salts does not change many properties of water (T/F).
  21. How is salinity measured?
    • Evaporation
    • Chemical analysis - Titration
    • Specific Gravity (w/ hydrometer) (1.028 g/ml)
    • Electrical conductivity (Salinometer, CTD)
  22. Coastal areas salinity varies more
    • widely in what ways?
    • Influx of freshwater lowers salinity or creates brackish conditions
    • Greater rate of evaporation raises salinity or creates hypersaline conditions
    • Salinity may vary with seasons (dry/rain).
  23. Processes that decrease salinity:
    • Precipitation (rain or snow)
    • Runoff (river flow)
    • Melting Icebergs
    • Melting sea ice
  24. Processes that increase salinity:
    • Evaporation
    • Formation of sea ice
  25. How are dissolved substances added to oceans?
    • River input (primarily)
    • Thermal vents
    • Volcanic eruptions
  26. How are dissolved substances removed from oceans?
    • Salt spray (minor)
    • Subduction at trenches (Geologic processes)
    • Biogenic sediments (Biological processes)
    • Evaporites (Chemical processes)
  27. Is the ocean becoming progressively saltier with age?
    • The proportion and amounts
    • of dissolved solids remain constant. This concept is known as the
    • “steady state ocean.“
    • Ions are being added to and removed from the ocean at the same rate.
  28. What does the hydrologic cycle describe?
    recycling of water near Earth's surface.
  29. Processes that add dissolved substances (salinity increases)
    • River flow
    • volcanic eruptions
    • atmosphere
    • biologic interactions
  30. processes that subtract dissolved substances (salinity decreases)
    • Chemical at seawater-sea floor interface
    • Biologic interactions
    • Evaporite formation
    • absorption
  31. Residence time
    Average length of time a substance remains dissolved in seawater.
  32. pH of seawater DOES NOT vary slightly with depth
    • (T/F)?
    • False
  33. What is the function of Carbonate Buffering?
    Keeps ocean pH about the same.
  34. Carbonate Buffering: describe the process
    • H2O + CO2 > H2CO3 > H+ + HCO3
    • ‐ > 2H+ + CO3
    • 2‐
    • Precipitation/dissolution of calcium carbonate (CaCO3) buffers ocean pH (CaCO3 > Ca+ + CO3
    • ‐)
    • Oceans can absorb CO2 from atmosphere without much
    • change in pH
  35. Surface ocean varies primarily with latitude (T/F)?
  36. Polar regions have slightly lower salinity, why is this?
    Lots of rain/snow and runoff
  37. Mid-latitudes have higher salinity, why is this?
    Evaporation and dry weather
  38. Equator has slightly lower salinity, why is this?
    Lots of rain
  39. The surface ocean salinity is NOT variable (T/F)?
  40. Deeper ocean salinity is the same (T/F)?
  41. Halocline
    rapid change of salinity with depth
  42. What is the density of seawater?
    1.022 to 1.030 g/cm3 surface seawater
  43. How is the ocean layered?
    according to density
  44. How is the density of seawater controlled?
    • Temp.
    • Salinity
    • Pressure
  45. Of Temperature, Salinity, and Pressure, what has the greatest amount of influence on seawater's density?
    • Temperature.
    • Density increases with decreases temperature.
  46. In what region does salinity have the greatest influence on the density of seawater?
    Polar oceans where polar ocean is isothermal (same temperature).
  47. Density differences cause a layered ocean (T/F)?
  48. Pynocline
    abrupt change of density with depth
  49. Thermocline
    abrupt change of temperature with depth
  50. Properties of a layered ocean
    • Mixed surface water
    • Pynocline
    • Thermocline
    • Deep water
    • High latitude oceans (Isothermal + isopycnal)
  51. Name a few Desalination processes
    • Distillation
    • Reverse osmosis
  52. Attenuation
    A process of scattering and absorbing weakened light
  53. What does Z I K stand for?
    • Z=depth
    • I=intensity
    • K=constant
  54. Scattering
    occurs when light is bounced between air and water molecules, dust and other objects.
  55. Absorption
    occurs when light's electromagnetic energy is converted to heat in the molecules of seawater.
  56. Colors are absorb at different rates:
    • Red first
    • Blue last
  57. Characteristics of sound in the ocean:
    • 25x faster than on land
    • directionless to humans