Marine Production of DMS and its Interaction with Climate

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Marine Production of DMS and its Interaction with
Climate

• Meike Vogt
• University of East Anglia (UEA) and MP-BGC
• Supervision
• Peter Liss
• Corinne Le Quéré
• In collaboration with Michael Steinke, Sue
  Turner, Erik Buitenhuis, Laurent Bopp, Sergio
  Vallina, Jim Gunson, CODIM Consortium, members of
  the Dynamic Green Ocean Project

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The marine DMS cycle

• Gaia theory
• CLAW hypothesis
• Complex oceanic S cycle
• Many ecosystem compartments involved
• phytoplankton
• zooplankton
• bacteria
• Processes
• Grazing, Mortality, Leakage
• Bacterial consumption,
• Photolysis

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Mesocosm Experiment DMS and Ocean Acidification

• CO2 enrichment experiment
• Study natural phytoplankton bloom under present,
  double, triple pCO2
• Reseach highlight DMS production affected by CO2
  concentration!

Vogt et al., submitted
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DMS Methods IntercomparisonPurge Trap versus
SolidPhaseMicroExtraction

• Most commonly used technique Purge Trap is
  laborious and equipment-expensive
• New technique (SPME) is inexpensive and easy to
  set up
• Research highlight
• Measurements are in very good agreement!
• New perspectives for large scale monitoring of
  DMS concentrations!

Vogt et al., to be submitted in April 2007
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Comparison of Ocean DImethylsulphide ModelsDMS
model intercomparison study (CODIM)

• Understanding the processes leading to DMS
  production The Summer Paradox
• Correlation maps between SeaWifs chlorophyll and
  Kettle DMS show
• DMS and chlorophyll concentrations delayed by 3
  months in between 40S and 40N?
• Why is that so? Why dont models capture this
  effect?

model
observation
Vézina et al., in preparation
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Global DMS ModellingModelling the DMS cycle in
PlankTOM5.1
PlankTOM5.1
Model ecosystem
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Global DMS ModellingModelling the DMS cycle in
PlankTOM5.1

• Apart from marine ecosystem composition
• Environmental conditions (T, Light) very
  important for DMS production (Vallina et al.,
  Science 02/2007)!
• Improvement of model formulations taking into
  account newly explored mechanisms (exudation) and
  causalities (stress)

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And if there are other DMS producers out
there.Well find you!
?
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Thank you!