david

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Adjunct Senior Research Scientist
Lamont-Doherty Earth Observatory
Geochemistry
61 Route 9W - PO Box 1000
Palisades
NY
10964-8000
US

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Fields of interest: 
Air-water gas exchange, tracer oceanography, transport in continental waters

To assess how human impact will affect the natural environment, we need to understand the relevant environmental processes. I have focused my studies on transport processes in natural systems (atmosphere, oceans, lakes, rivers and groundwater), using natural and anthropogenic tracers.

Tracers, whether they are of natural or anthropogenic origin, have the potential to be valuable tools for studies of the dynamics of the atmosphere and natural water systems. The tracer techniques that I have employed could be divided into two categories: 1) transient tracers, which are like 'dyes' with known delivery rates to the environment (CFCs, SF6), and 2) deliberate tracers, which are purposefully released into water bodies (SF6, N2O, 4He, 3He, florescent dyes).

I'm currently working in the following areas: Quantifying the effect of environmental variables on air-water gas exchange, developing of tracers for ocean mixing and circulation, and investigating transport and mixing in continental waters.

Some of my projects include:

  • Development of SF6 as a transient tracer for ocean circulation
  • Develop SF5CF3 as a deliberate tracer for ocean mixing
  • Air-Sea Gas Exchange investigations as part of SOLAS (Surface-Ocean Lower-Atmospheric Studies)
  • Studying sheetflow in the Florida Everglades
  • Studying transport and air-water gas exchange in the Hudson River Estuary

 

Education
List of degrees from highest to lowest:
Ph.D.
Columbia University
2001
M.Phil.
Columbia University
2000
M.A.
Columbia University
1997
B.A.
Columbia University
1994

Lamont Projects:

Selected Publications:

Advances in Quantifying Air-Sea Gas Exchange and Environmental Forcing Wanninkhof, R.; Asher, W. E.; Ho, D. T.; Sweeney, C.; McGillis, W. R. Annual Review of Marine Science Volume: 1 p.: 213-244 (2009) DOI 10.1146/annurev.marine.010908.163742
Rain-induced turbulence and air-sea gas transfer Zappa, C. J.; Ho, D. T.; McGillis, W. R.; Banner, M. L.; Dacey, J. W. H.; Bliven, L. F.; Ma, B.; Nystuen, J. Journal of Geophysical Research-Oceans Jul 9 Volume: 114 p.: - (2009) Doi 10.1029/2008jc005008
Degradation rates of CFC-11, CFC-12 and CFC-113 in anoxic shallow aquifers of Araihazar, Bangladesh Horneman, A.; Stute, M.; Schlosser, P.; Smethie, W.; Santella, N.; Ho, D. T.; Mailloux, B.; Gorman, E.; Zheng, Y.; van Geen, A. Journal of Contaminant Hydrology Apr 4 Volume: 97 Issue: 1-2 p.: 27-41 (2008) DOI 10.1016/j.jconhyd.2007.12.001
Use of SF5CF3 for ocean tracer release experiments Ho, D. T.; Ledwell, J. R.; Smethie, W. M. Geophysical Research Letters Feb 19 Volume: 35 Issue: 4 p.: - (2008) Doi 10.1029/2007gl032799
Widespread elevated atmospheric SF6 mixing ratios in the Northeastern United States: Implications for groundwater dating Santella, N.; Ho, D. T.; Schlosser, P.; Stute, M. Journal of Hydrology Jan 30 Volume: 349 Issue: 1-2 p.: 139-146 (2008) DOI 10.1016/j.jhydrol.2007.10.031
An SF6 Tracer Study of the Flow Dynamics in the Stockton Deep Water Ship Channel: Implications for Dissolved Oxygen Dynamics Schmieder, P.J.; Ho, D.T.; Schlosser, P; Clark, J.F.; Schladow, S.G. Estuaries and Coasts Volume: 31 p.: 14 (2008) 10.1007/s12237-008-9093-0
Degradation rates of CFC-11, CFC-12 and CFC-113 in anoxic shallow aquifers of Araihazar, Bangladesh Horneman, A.; Stute, M.; Schlosser, P.; Smethie, W.; Santella, N.; Ho, D. T.; Mailloux, B.; Gorman, E.; Zheng, Y.; van Geen, A. Journal of Contaminant Hydrology Apr 4 Volume: 97 Issue: 1-2 p.: 27-41 (2008) DOI 10.1016/j.jconhyd.2007.12.001
The combined effect of rain and wind on air-water gas exchange: A feasibility study Ho, D. T.; Veron, F.; Harrison, E.; Bliven, L. F.; Scott, N.; McGillis, W. R. Journal of Marine Systems Jun Volume: 66 Issue: 1-4 p.: 150-160 (2007) DOI 10.1016/j.jmarsys.2006.02.012
Environmental turbulent mixing controls on air-water gas exchange in marine and aquatic systems Zappa, C. J.; McGillis, W. R.; Raymond, P. A.; Edson, J. B.; Hintsa, E. J.; Zemmelink, H. J.; Dacey, J. W. H.; Ho, D. T. Geophysical Research Letters May 17 Volume: 34 Issue: 10 p.: - (2007) Doi 10.1029/2006gl028790
Comparison of SF6 and fluorescein as tracers for measuring transport processes in a large tidal river Ho, D. T.; Schlosser, P.; Houghton, R. W.; Caplow, T. Journal of Environmental Engineering-Asce Dec Volume: 132 Issue: 12 p.: 1664-1669 (2006) Doi 10.1061/(Asce)0733-9372(2006)132:12(1664)
Measurements of air-sea gas exchange at high wind speeds in the Southern Ocean: Implications for global parameterizations Ho, D. T.; Law, C. S.; Smith, M. J.; Schlosser, P.; Harvey, M.; Hill, P. Geophysical Research Letters Aug 25 Volume: 33 Issue: 16 p.: - (2006) Doi 10.1029/2006gl026817
Seasonal variability and long term trends of chlorofluorocarbon mixing ratios in the unsaturated zone Santella, N.; Schlosser, P.; Smethie, W. M.; Ho, D. T.; Stute, M. Environmental Science & Technology Jul 15 Volume: 40 Issue: 14 p.: 4414-4420 (2006) Doi 10.1021/Es052376o
Effect of tides on solute flushing from a strait: Imaging flow and transport in the East River with SF6 Caplow, T.; Schlosser, P.; Ho, D. T.; Enriquez, R. C. Environmental Science & Technology Sep 1 Volume: 38 Issue: 17 p.: 4562-4571 (2004)
Influence of rain on air-sea gas exchange: Lessons from a model ocean Ho, D. T.; Zappa, C. J.; McGillis, W. R.; Bliven, L. F.; Ward, B.; Dacey, J. W. H.; Schlosser, P.; Hendricks, M. B. Journal of Geophysical Research-Oceans Jul 1 Volume: 109 Issue: C8 p.: - (2004) Doi 10.1029/2003jc001806
Tracer study of mixing and transport in the upper Hudson River with multiple dams Caplow, T.; Schlosser, P.; Ho, D. T. Journal of Environmental Engineering-Asce Dec Volume: 130 Issue: 12 p.: 1498-1506 (2004) Doi 10.1061/(Asce)0733-9372(2004)130:12(1498)
Transport in the Hudson estuary: A modeling study of estuarine circulation and tidal trapping Hellweger, F. L.; Blumberg, A. F.; Schlosser, P.; Ho, D. T.; Caplow, T.; Lall, U.; Li, H. H. Estuaries Jun Volume: 27 Issue: 3 p.: 527-538 (2004)
Distribution of atmospheric SF6 near a large urban area as recorded in the vadose zone Santella, N; Ho, DT; Schlosser, P; Stute, M Environmental Science & Technology Mar 15 Volume: 37 Issue: 6 p.: 1069-1074 (2003) Doi 10.1021/Es0156993
Transport dynamics in a sheltered estuary and connecting tidal straits: SF6 tracer study in New York Harbor Caplow, T.; Schlosser, P.; Ho, D. T.; Santella, N. Environmental Science & Technology Nov 15 Volume: 37 Issue: 22 p.: 5116-5126 (2003) Doi 10.1021/Es034198+
Determination of longitudinal dispersion coefficient and net advection in the tidal Hudson River with a large-scale, high resolution SF6 tracer release experiment Ho, D. T.; Schlosser, P.; Caplow, T. Environmental Science & Technology Aug 1 Volume: 36 Issue: 15 p.: 3234-3241 (2002) UNSP ES015814+
Atmospheric SF6 near a large urban area Ho, D. T.; Schlosser, P. Geophysical Research Letters Jun 1 Volume: 27 Issue: 11 p.: 1679-1682 (2000)
On mechanisms of rain-induced air-water gas exchange Ho, D. T.; Asher, W. E.; Bliven, L. F.; Schlosser, P.; Gordan, E. L. Journal of Geophysical Research-Oceans Oct 15 Volume: 105 Issue: C10 p.: 24045-24057 (2000)
Variability in atmospheric chlorofluorocarbons (CCl3F and CCl2F2) near a large urban area: Implications for groundwater dating Ho, D. T.; Schlosser, P.; Smethie, W. M.; Simpson, H. J. Environmental Science & Technology Aug 15 Volume: 32 Issue: 16 p.: 2377-2382 (1998)
The effect of rain on air-water gas exchange Ho, D. T.; Bliven, L. F.; Wanninkhof, R.; Schlosser, P. Tellus Series B-Chemical and Physical Meteorology Apr Volume: 49 Issue: 2 p.: 149-158 (1997)
Gas exchange, dispersion, and biological productivity on the west Florida shelf: Results from a Lagrangian tracer study Wanninkhof, R.; Hitchcock, G.; Wiseman, W. J.; Vargo, G.; Ortner, P. B.; Asher, W.; Ho, D. T.; Schlosser, P.; Dickson, M. L.; Masserini, R.; Fanning, K.; Zhang, J. Z. Geophysical Research Letters Jul 15 Volume: 24 Issue: 14 p.: 1767-1770 (1997)
Gas Transfer Velocities for Sf6 and He-3 in a Small Pond at Low Wind Speeds Clark, J. F.; Schlosser, P.; Wanninkhof, R.; Simpson, H. J.; Schuster, W. S. F.; Ho, D. T. Geophysical Research Letters Jan 15 Volume: 22 Issue: 2 p.: 93-96 (1995)