FATE

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Future Applications of 234Th in aquatic Ecosystems
(FATE)
August 16-19, 2004 Woods Hole, MA
Sponsored by the National Science Foundation
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11-16 Gt C/y results in an atm CO2 150 to 200 ppm
lower than if all the phytoplankton in the ocean
were to die
Phytoplankton
N,P,Fe
CO2
Bacteria
DOM
Zooplankton
Euphotic Zone
Settling Particles
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The purpose of the workshop is to bring together
a number of international experts in the
collection and application of 234Th in aquatic
ecosystems with diverse opinions and backgrounds
to discuss and define current concepts in the use
of 234Th and a coherent strategy for future
applications.
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1998 San Diego AGU/ASLO Ocean Sciences Meeting
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• New methodologies and techniques
• What are the current methods for collecting and
  measuring 234Th in fresh and marine ecosystems?
• What is the best way to convert these
  measurements into integrated 234Th deficiencies?
• Can we assess and reduce the uncertainty in
  making this conversion?

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• C/234Th ratios
• How should C/234Th ratios be collected and
  measured? 
• Are all phases of POC in equilibrium with
  234Th? 
• Can POC fluxes inferred from 234Th be biased by
  cycling of 234Th through a limited portion of the
  POC pool that has a turnover time significantly
  different from that of the "average" POC? 
• How should 234Th results be compared to other
  indices of sinking particle flux? 

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• Modeling
• What are the appropriate models for
  understanding particle residence times,
  aggregation/coagulation rates, and sinking losses
  of 234Th? 
• Do current models deal adequately with 3-D
  transport of 234Th (both particulate and
  dissolved) and with temporal variability of the
  processes involved?

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• 234Th speciation in seawater
• What is the speciation of 234Th with respect to
  dissolved and particulate inorganic and organic
  phases in seawater? How does 234Th speciation
  impact aggregation and flux?
• Can a better understanding of the geochemistry
  of 234Th improve our use of 234Th as a particle
  cycling and flux proxy? Are all phases of 234Th
  in chemical equilibrium with one another? 
• What is necessary to achieve this better
  understanding?

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Today A series of introductory talks to provoke
thought and discussion on each of the
topics. Tuesday-Thursday Discussion and plan
for answering these questions
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• Outcome
• A series of papers within a special volume that
• Address what was discussed at the meeting, i.e.
  overview and future directions
• Current research being conducted by our
  community.