1. Mass Confusion About Air-Water Mass Transfer Damon Turney Bren School of Environmental Science and Management Committee Members: Jeff Dozier, Sanjoy Banerjee, Sally MacIntyre, Jordan Clark

2. Fate and Transport - Carbon - Toxins (DDT, Hg, Dieldrin, PCBs, many more) - Aeration of Hypoxic Water - DeAeration of Water Below Dam Spillways - Industrial Cleaning of Water in Air Spargers - Bioreactors and Other Reactors in Industry - Steam Condensation in Power Plants

4. from Wanninkhof et al. 1992 from Rosso 2006 from Kelly 1997

5. Convection + Diffusion

6. Convection + Diffusion = Confusion

7. advectiondiffusion

8. advectiondiffusion

9. Air Water Advection into the water is not possible

10. Air Water Advection into the water is not possible Diffusion

11. Air Water Diffusion is ~10 -9 m 2 /s Diffusion is ~10 -5 m 2 /s Advection into the water is not possible Diffusion

13. Air Water

15. Surface Renewal Theory No unambiguous way of determining a value for average t

16. Surface Divergence Theory

17. 1 mm

18. Surface Divergence Theory 100 μm

19. Surface Divergence Theory 1 mm

21. Surface Divergence Theory

23. How do we visualize (or measure) the velocities in the top ~100 microns of the water column accurately?

24. Surface Divergence Theory from Turney et al. 2005 from McKenna & McGillis 2004

25. Surface Divergence Theory from Xu et al. 2006 from Turney et al. 2005

30. Experimental Conditions No Wind, Channel Flow (Straight Channelized River) 4 water heights 3 water velocities Reynolds numbers ranging from 5000 to 30,000 Wind Waves, Microscale Wave Breaking 10 wind speeds fetch constant ~9 meters

31. Measurements No Wind, Channel Flow - Mean Velocity, Depth, Temperature, - PIV Turbulence in Middle of Water Column - Friction of Water on Channel Bottom - PIV of Surface Divergence Motions - Oxygen Transfer Measurements Wind Waves - Mean Velocity, Depth, Temperature, - PIV Turbulence in Middle of Water Column - Friction of Water on Channel Bottom - Wind Speeds (~1mm apart) at Locations Above Interface - Friction of Wind on Air-Water Interface - Stereo PIV of Surface Divergence Motions - Oxygen Transfer Measurements - Standard Water Height Measurements and Shadowgraphs

34. u* (cm/s) k 10 -5 (cm/s)

41. k=3.3 x 10 -5 m/s F=3.3 x 10 -5 ΔC

43. Conclusions: It’s possible that the Surface Divergence Models is too simple, i.e., it ignores organized flows such as waves. Perhaps it is time for a new theory. Time-history effects are necessary for an adequate understanding of how the chemical is transported away from the interface. Accurate knowledge of velocity near the interface is very valuable. These measurement techniques should be pushed forward.

44. The Bigger Picture and Future Work

50. Pg C: 3.2 (+/-0.2) = 6.3 (+/-0.4) + 2.2(+/-1.3) - 2.4(+/-1.2) – 2.9 atmosphere fossil fuel terrestrial oceanic error from Sabine et al. 2004 from Woods Hole Website

51. 1 cm Air Water

52. from Herlina & Jirka 2004

53. Air Water 1 cm

55. from Tokoro et al 2007 from Belanger 1991

57. Surface Divergence Theory 1 mm

58. Surface Divergence Theory 1 mm

59. Surface Divergence Theory 1 mm

60. Surface Divergence Theory 1 mm

61. Surface Divergence Theory 1 mm

62. Surface Divergence Theory 1 mm

63. Surface Divergence Theory 1 mm

64. Surface Divergence Theory 1 mm

65. Depth (cm)Flow Speed (cm/s) Macro ReTurbulent Re 5 2.3 1150 5 3.0 1510 5 10.0 5000 100 5 24.0 12000 170 5 54.5 30000 310 7 7.1 5000 100 7 17.1 12000 170 7 42.9 30000 280 9 5.6 5000 80 9 13.3 12000 140 9 33.3 30000 250 10 5.8 5800 10 10.7 10700 13 3.8 5000 50 13 9.2 12000 100 13 23.1 30000 190 No Wind

66. Depth (cm)Wind Speed (cm/s) Wave Height (cm) 5 75 - 5 165 - 5 224 - 5 291 - 10 319 - 10 410 0.2 10 499 0.4 10 599 0.6 10 712 0.7 10 706 0.7 10 799 0.9 10 894 1.1 Windy

69. from Takahashi et al. 2008

70. from Richey et al. 2002

71. Chemical Budgets Change in Amount per Unit Time = Flux In - Flux Out

72. Surface Renewal Theory

73. Surface Divergence Theory 1 mm

74. Surface Divergence Theory 100 μm

75. Surface Divergence Theory 1 mm

76. Surface Divergence Theory 1 mm

77. Surface Divergence Theory

80. Pg C: 3.2 (+/-0.2) = 6.3 (+/-0.4) + 2.2(+/-1.3) - 2.4(+/-1.2) – 2.9 atmosphere fossil fuel terrestrial oceanic error Chemical Budgets Change in Amount per Unit Time = Flux In - Flux Out

83. from Blais et al. 2001

87. from Schimpf et al. 2004

89. from Herlina & Jirka 2004

90. Surface Renewal Theory

91. “Renewed” Spot

92. Surface Renewal Theory “Renewed” Spot

93. Surface Renewal Theory