Halogenated Trace Gases

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Halogenated Trace Gases and Isoprene R. M. Moore
L. Wang
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Isoprene
t
2-methylbuta-1,3-diene

• trace gas produced by all marine algae
• atmospheric concentration 0

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Methyl chloride
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Methyl chloride
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Methyl bromide
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Methyl iodide
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Methyl iodide
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What was learned?
Possible sources of CH3X Phytoplankton Halide
reaction with DMSP Photochemistry Bacteria Zoop
lankton
CH3X production limited to certain species - not
significantly produced by Pseudonitzschia (?)
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What was learned?
Possible sources of CH3X Phytoplankton X-
reaction with DMSP Photochemistry Bacteria Zoop
lankton
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Proposed pathway for MeX production White (1982)
Kinetic study ( Hu Moore 1996) indicated that
this reaction could account for 10-3 of CH3Cl
flux to atmosphere
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What was learned?
Possible sources of CH3X Phytoplankton X-
reaction with DMSP Photochemistry Bacteria Zoop
lankton
No evidence
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What was learned?
Possible sources of CH3X Phytoplankton X-
reaction with DMSP Photochemistry Bacteria Zoop
lankton
Results not inconsistent with photochemical
production
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What was learned?
Possible sources of CH3X Phytoplankton X-
reaction with DMSP Photochemistry Bacteria Zoop
lankton
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Incubating samples with copepods did not Cause
significant change in CH3X