wg b2: water column transport and _air-sea fluxes cost action pergamon kick off, bruxelles, nov....
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WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
WG-B2: Effectiveness of methane transport through the water column (ocean and lakes) and assessment of
methane flux into the atmosphere
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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• Input into the water column• Spatio-temporal variations• Changes due to enhanced anthropogenic forcing
• Gas transport through the water column• Dissolution and gas invasion• Impact of oil and organic films• Plume dynamics• Saturation potential (Lakes, Lake Nyos scenario)
• Gas transport in the water column• Circulation• Stratification
• Aerobic oxidation in water column• Turnover rates as a function of T and CMethane
• Adaptation time scale• Oxidation at the water ice interface
• Ice cover related questions• Gas migration through and along ice• Temporal release
• Air Sea Exchange• Interplay of ice cover, stratification, and wind
field in a spatio-temporal framework
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
Modified from Schneider von Deimling, PhD thesis, University Kiel, 2009
CH4 in the water column: where do we start with?
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WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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From Shakhova and Semiletov, Arctic workshop Texel, 2009
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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• Gas transport through the water column• Dissolution and gas invasion• Impact of oil and organic films• Plume dynamics• Saturation potential (Lakes, Lake Nyos
scenario)
• Various gas migration models with still large differences in parameterization (McGinnes, Leifer, Zhang and Yapa…)• Streamlining• Gap in experimental parameterization?• Plume model characteristics usually not
straightforward• We are dealing with shallow waters, so is it
an issue for a time-averaged flux, or just for annual pulsing?
• Behavior of gas trapped under ice
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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• Gas transport in the water column
• Circulation• Stratification
From Shakhova and Semiletov, Arctic workshop Texel, 2009
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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• Gas transport in the water column
• Circulation• Stratification
From Shakhova and Semiletov, Arctic workshop Texel, 2009
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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• Aerobic oxidation in water column• Turnover rates as a function of T and CMethane
• Adaptation time scale• Oxidation at the water ice interface
Turnovertimes for methane oxidation in the water column, various sources
•Decrease in turnover rates with decreasing concentrations
• Faster specific oxidation rates at same concentrations in warmer settings
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
9
• Ice cover related questions
• Gas migration through and along ice
• Temporal release (giving crucial time scale)
• Oxidation at the water ice interface
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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Sea-ice change
• Changes ASE-protected time slot• Changes freshwater dynamics (stratification)
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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• Air Sea Exchange• Interplay of ice cover, stratification, and wind
field in a spatio-temporal framework
Regional circulation model with wind field and ice model available?
Can remote sensing do a better job?
WG B2: Water Column Transport and _Air-Sea Fluxes
Cost Action PERGAMON Kick Off, Bruxelles, Nov. 12-13, 2009
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The area is just to big for the usual approaches