Coastal Environments: The Basics
• 97% of all water on our planet is in theoceans.• Fresh water represents the remaining 3%(2/3 is snow and ice in glaciers...
Unique properties of water• Absorbs or releases more heat than most  other substances for every temperature  degree of cha...
More than half the worlds population live within 60km of a coastline[In the US, half live within   80 km, on less than 17%...
Overview• Chemical properties of water   – H bonds   – Ice   – Salinity and Sources• Physical properties of water   – Biom...
Chemical properties of waterA.   Hydrogen Bonds          E.   Specific HeatB.   Crystalline Structure   F.   EvaporationC....
Chemical properties of waterA.   Hydrogen Bonds          E.   Specific HeatB.   Crystalline Structure   F.   EvaporationC....
Hydrogen Bonds        O d- d+ H          H d+
Hydrogen Bonds
Hydrogen Bonds3 physical states of water:      WATER VAPOR
Crystalline Structure
Crystalline Structure
Ice
Surface tensionWater has high surface tension due tolateral and downward attraction betweenindividual molecules, which str...
Surface tensionWater has high surface tension due tolateral and downward attraction betweenindividual molecules, which str...
Surface tension• Water striders can walk upon the waters surface.• Members of the neuston depend upon the surface film ofw...
Tensile strength           Water is strong under tension.The force needed to pull pure water apart can be as    much as 3 ...
Specific heatWater can absorb a great deal of energy which goes tobreaking hydrogen bonds but does not lead to measurablet...
Evaporation   A water molecule makes the transition from    a liquid phase into a gas phase.Because the escaping molecule...
Hydrogen Bonds - Summary•   High heat capacity (1 cal/g/C);•   Heat of vaporization (540 cal/g);•   Heat of fusion (-80 c...
Molecular interactionsSolutes  Dissociation of Water Molecules      KD = [H+][OH-]/[H2O] = 1.8 x 10-16 Mwhere KD is the di...
pH of solutionspH - an index of the relative concentration of H+ ions in solution[H+] = [OH-] = 10-7 M in pure water    ([...
pH of solutions•   The pH scale ranges from 0 to 14•   The higher the pH, the lower the [H+]    (alkaline, basic solutions...
pH of solutionsExamples:Gastric juice = 1.0   Seawater  8.0Orange juice = 4.3    Urine = 6-8.0Blood plasma = 7.4    Ammon...
pH and the sea• A difference in pH from 8 to 7.8 can  significantly decrease coral growth rates• Increased CO2 in the atmo...
Water as a polar solvent and SalinityStrong Electrolytes (substances that dissociate    completely when dissolved in water...
Water as a polar solventWeak Electrolytes (substances that dissociate in   water only to a small extent (KD  10-3 M to   ...
Carbon dioxide-carbonate equilibrium         CO2(g)        CO2(aq)     (CO2 from the atmosphere                           ...
Water as a polar solventBecause of its small size and polar nature, water   dissolves many materials, more than any other ...
Seawater constituentsComponent     Concentration Percentage of Salinity chloride         18.98              55.03  sodium ...
Seawater constituents•Average ocean water has a salinity of 35.0•This means that 1000 g of average seawater contains 965 g...
Dissolved                                        chemicals                Wind, water, and                                ...
Seawater constituents
Seawater constituents
Seawater constituentsFrom U.S. Geological Survey Open-File Report 03–028, January2003 African Dust Carries Microbes Across...
Movement and TransportDiffusion – high concentrations  low concentration    Air vs. waterMass transport – particles carri...
Diffusionhigh concentration  low concentration                       C = concentration                       D = diffusio...
Mass Transporthigh concentration  low concentration
Physical properties of water  •Viscosity  •Reynolds number, Boundary  Layers, and Mass transport  •Density  •Temperature
Water as a fluidFluid (flu·id) French fluide, from Latin fluidus,from fluere to flow; akin to Greek phlyzein to boilover):...
What is a fluid?Viscosity (m): the resistance of a fluid to motion or internalfrictionReynolds number (Re): the ratio of i...
Viscosity   The viscosity of liquids can vary drastically and   decreases rapidly with an increase in temperature.  m = 50...
Reynolds number
Reynolds number  Re = rUx/m
Reynolds number                     Re = rUx/m                 Re = 108Re = 1
Copepod swimming      Low Re
Boundary Layers and Mass TransportRe = 101              Laminar       Turbulent
Boundary Layers
Boundary Layers and Mass TransportRe = 103Re = 108
Major basins
Major basins        4                     2    1                           35
Major basins –               General CharacteristicsPacific Ocean                           Indian Ocean• average depth 3,...
Marginal SeasSurrounding the Atlantic Ocean is the Sargasso Sea (1), Weddell Sea (2), the   Caribbean Sea (3), the North S...
Largest, smallest, deepest, saltiestThe Arctic Ocean is thesmallest (area = 9,485,000sq km, or < 1/10 Pacific) Pacific Oce...
Top 10 Deepest Trenches1 Mariana2 Tonga3 Philippine4 Kermadec            81                   9                    355 Bon...
Puerto Rico Trench               8,400 m (5.2 miles)
Highest SalinityRed Sea salinity rangesbetween 36 and 38 psuDead Sea salinity = 360 psu
Ocean basins
Ocean basins
Ocean basinsTo “sail the seven seas” (< 1400’s) =   1. Adriatic Sea   2. Black Sea   3. Caspian Sea   4. Mediterranean Sea...
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Ocean basics

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Chemical and Physical Properties of water

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Ocean basics

  1. 1. Coastal Environments: The Basics
  2. 2. • 97% of all water on our planet is in theoceans.• Fresh water represents the remaining 3%(2/3 is snow and ice in glaciers / polar icecaps).• Liquid and solid water cover roughly 3/4 ofEarths surface area.• 29% of the earth’s surface is above sea level(71% is below )
  3. 3. Unique properties of water• Absorbs or releases more heat than most other substances for every temperature degree of change• Water is a good solvent and can dissolve more substances than other fluids, even rocks• Water exists in 3 physical states that can power thunderstorms/hurricanes and help transport the suns energy, nutrients, and organisms
  4. 4. More than half the worlds population live within 60km of a coastline[In the US, half live within 80 km, on less than 17% of the land area…] South Florida, USA
  5. 5. Overview• Chemical properties of water – H bonds – Ice – Salinity and Sources• Physical properties of water – Biomechanics – Density – Temperature• Major ocean basins of the world – Chemical signatures (depth and latitude)• Coastal Systems – Sandy beaches, rocky coasts, estuaries, deltas, reefs
  6. 6. Chemical properties of waterA. Hydrogen Bonds E. Specific HeatB. Crystalline Structure F. EvaporationC. Surface Tension G. Molecular InteractionsD. Tensile Strength H. Movement and Transport
  7. 7. Chemical properties of waterA. Hydrogen Bonds E. Specific HeatB. Crystalline Structure F. EvaporationC. Surface Tension G. Molecular InteractionsD. Tensile Strength H. Movement and Transport
  8. 8. Hydrogen Bonds O d- d+ H H d+
  9. 9. Hydrogen Bonds
  10. 10. Hydrogen Bonds3 physical states of water: WATER VAPOR
  11. 11. Crystalline Structure
  12. 12. Crystalline Structure
  13. 13. Ice
  14. 14. Surface tensionWater has high surface tension due tolateral and downward attraction betweenindividual molecules, which stretches thewaters surface, creating a thin skin O d- d+ H H d+
  15. 15. Surface tensionWater has high surface tension due tolateral and downward attraction betweenindividual molecules, which stretches thewaters surface, creating a thin skin
  16. 16. Surface tension• Water striders can walk upon the waters surface.• Members of the neuston depend upon the surface film ofwater for transport and food.• Liquid water on surfaces to which it does not adhere well"beads-up."• Surface tension of the water allows wind to push againstit, generating waves in large water bodies.• [Detergents reduce the surface tension of water (by asmuch as 70%) and allows it to spread out on a surface.]
  17. 17. Tensile strength Water is strong under tension.The force needed to pull pure water apart can be as much as 3 x 107 Newtons/m2120 lbs = 530 Newtons Limpet attachment strength = 1 x 106 Newtons/m2
  18. 18. Specific heatWater can absorb a great deal of energy which goes tobreaking hydrogen bonds but does not lead to measurabletemperature increases.Because of the massive number of hydrogen bonds in water,it requires a lot of energy to see even a small change inwater temperature.
  19. 19. Evaporation A water molecule makes the transition from a liquid phase into a gas phase.Because the escaping molecule had a higher than average energy level, it leaves the liquid cooler (lower in energy) upon evaporation.
  20. 20. Hydrogen Bonds - Summary• High heat capacity (1 cal/g/C);• Heat of vaporization (540 cal/g);• Heat of fusion (-80 cal/g);• Solid less dense than liquid phase;• High surface tension
  21. 21. Molecular interactionsSolutes Dissociation of Water Molecules KD = [H+][OH-]/[H2O] = 1.8 x 10-16 Mwhere KD is the dissociation constant (equilibrium constant) for the dissociation of a proton from a water molecule (the smaller the KD, the stronger the binding)
  22. 22. pH of solutionspH - an index of the relative concentration of H+ ions in solution[H+] = [OH-] = 10-7 M in pure water ([H2O] = 55 M)pH  -log10[H+]In pure water, pH = 7
  23. 23. pH of solutions• The pH scale ranges from 0 to 14• The higher the pH, the lower the [H+] (alkaline, basic solutions have a high pH)• The lower the pH, the higher the [H+] (acidic solutions have a lower pH)
  24. 24. pH of solutionsExamples:Gastric juice = 1.0 Seawater  8.0Orange juice = 4.3 Urine = 6-8.0Blood plasma = 7.4 Ammonia = 12.0
  25. 25. pH and the sea• A difference in pH from 8 to 7.8 can significantly decrease coral growth rates• Increased CO2 in the atmosphere lowers pH• Active photosynthesis and nitrogenous waste excretion can increase local pH
  26. 26. Water as a polar solvent and SalinityStrong Electrolytes (substances that dissociate completely when dissolved in water - ions) Salts consist of ions: NaCl  Na+ + Cl- salt HCl  H+ + Cl- strong acid NaOH  Na+ + OH- strong base For strong electrolytes, KD  
  27. 27. Water as a polar solventWeak Electrolytes (substances that dissociate in water only to a small extent (KD  10-3 M to 10-11 M) H2CO3  H+ + HCO3- KD = 1.7 x 10-4 M KD  10-3 M to 10-11 M
  28. 28. Carbon dioxide-carbonate equilibrium CO2(g) CO2(aq) (CO2 from the atmosphere dissolves into seawater)CO2(aq) + H2O(l) H2CO3(aq) (Carbonic acid) bicarbonate H2CO3 H+ + HCO3- KD = 4.2 × 10-7 carbonate HCO3- H+ + CO32- KD = 4.8 × 10-11 CaCO3(s) + 2 H+(aq) Ca2+(aq) + H2CO3(aq) High CO2= low [CO32- ] Ocean acidification
  29. 29. Water as a polar solventBecause of its small size and polar nature, water dissolves many materials, more than any other liquidOceans of water act as sink for CO2 molecules – leads to acidificationSeawater contains almost every known naturally occurring element
  30. 30. Seawater constituentsComponent Concentration Percentage of Salinity chloride 18.98 55.03 sodium 10.56 30.59 sulfate 2.65 7.68magnesium 1.27 3.68 calcium 0.40 1.18potassium 0.38 1.11bicarbonate 0.14 0
  31. 31. Seawater constituents•Average ocean water has a salinity of 35.0•This means that 1000 g of average seawater contains 965 gof water and 35 g of salts.
  32. 32. Dissolved chemicals Wind, water, and ice erosion Biological uptake, or absorption of particles, or precipitation Eroded rock particles Wind, water, and ice erosion Seawater River and wind transport and depositionconstituents Sediments Fallout of volcanic ash over oceans Volcanic ash and igneous rocks on land Compaction and water loss Subduction, melting, and vulcanism Scraped of and uplifted ot subduction zone Sedimentary rock Sedimentary rock on oceanic crust on land
  33. 33. Seawater constituents
  34. 34. Seawater constituents
  35. 35. Seawater constituentsFrom U.S. Geological Survey Open-File Report 03–028, January2003 African Dust Carries Microbes Across the Ocean: Are TheyAffecting Human and Ecosystem Health?
  36. 36. Movement and TransportDiffusion – high concentrations  low concentration Air vs. waterMass transport – particles carried by fluid flow
  37. 37. Diffusionhigh concentration  low concentration C = concentration D = diffusion coefficient x = length t = time
  38. 38. Mass Transporthigh concentration  low concentration
  39. 39. Physical properties of water •Viscosity •Reynolds number, Boundary Layers, and Mass transport •Density •Temperature
  40. 40. Water as a fluidFluid (flu·id) French fluide, from Latin fluidus,from fluere to flow; akin to Greek phlyzein to boilover):  having particles that easily move and change theirrelative position without a separation of the mass andthat easily yield to pressure; capable of flowing.
  41. 41. What is a fluid?Viscosity (m): the resistance of a fluid to motion or internalfrictionReynolds number (Re): the ratio of inertial forces to viscousforces in a fluidDensity (r): the mass of a substance per unit volume
  42. 42. Viscosity The viscosity of liquids can vary drastically and decreases rapidly with an increase in temperature. m = 50 N s/m2 At 20º C m = 1 x 10-3 N s/m2m = 0.07 N s/m2 At 100º C
  43. 43. Reynolds number
  44. 44. Reynolds number Re = rUx/m
  45. 45. Reynolds number Re = rUx/m Re = 108Re = 1
  46. 46. Copepod swimming Low Re
  47. 47. Boundary Layers and Mass TransportRe = 101 Laminar Turbulent
  48. 48. Boundary Layers
  49. 49. Boundary Layers and Mass TransportRe = 103Re = 108
  50. 50. Major basins
  51. 51. Major basins 4 2 1 35
  52. 52. Major basins – General CharacteristicsPacific Ocean Indian Ocean• average depth 3,940 m • average depth 3,840 m• extensive marginal seas, volcanic • large sediment input (Indus and Ganges island systems, and trenches River Deltas) Arctic Ocean• considerable mountain building and earthquake activity along • average depth 1,038 m boundaries (Ring of Fire) • centered on the north pole• little freshwater input • shallow and land-locked • covered by sea iceAtlantic Ocean • large sediment input from active glaciers• average depth 3,310 m Southern Ocean• large freshwater input (Amazon, • average depth 4,000 m Congo, Mississippi, Niger, Orinoco • continuous ring of water around Antarctica Rivers) • coldest of all oceans (near freezing) • extensive winter sea ice coverage • most biologically productive ocean
  53. 53. Marginal SeasSurrounding the Atlantic Ocean is the Sargasso Sea (1), Weddell Sea (2), the Caribbean Sea (3), the North Sea (4), and the Mediterranean Sea (5). Surrounding the Pacific Ocean is the Ross Sea (6), the Coral Sea (7), the South China Sea (8), the Sea of Japan (9), the Sea of Okhotsk (10), the Bering Sea (11), and the Sea of Cortez (12) (also called the Gulf of California). Surrounding the Indian Ocean is the Red Sea (13), the Arabian Sea (14), and the Bay of Bengal (15). Surrounding the Arctic Ocean is the Bering Sea (11), the Laptev Sea (16), the Barents Sea (17), and the Beaufort Sea (18).
  54. 54. Largest, smallest, deepest, saltiestThe Arctic Ocean is thesmallest (area = 9,485,000sq km, or < 1/10 Pacific) Pacific Ocean = 1/3 globe (18 x US) 1/2 world ocean
  55. 55. Top 10 Deepest Trenches1 Mariana2 Tonga3 Philippine4 Kermadec 81 9 355 Bonin 7 10 6 26 New Britain 47 Kuril8 Izu9 Puerto Rico10 Yap Mariana Trench = 35,802 ft (10,912 m)
  56. 56. Puerto Rico Trench 8,400 m (5.2 miles)
  57. 57. Highest SalinityRed Sea salinity rangesbetween 36 and 38 psuDead Sea salinity = 360 psu
  58. 58. Ocean basins
  59. 59. Ocean basins
  60. 60. Ocean basinsTo “sail the seven seas” (< 1400’s) = 1. Adriatic Sea 2. Black Sea 3. Caspian Sea 4. Mediterranean Sea 5. Red Sea 6. Persian Gulf 7. Indian Ocean

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