Research Interests &ndash Atmospheric Chemistry

Time Series for SF6 at the Clean-Air Measurement Stations at Cape Grim and Trinidad Head (update: 1/2004)

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We have been analyzing sulfur hexafluoride (SF6) from flasks samples collected at the Cape Grim Observatory, Tasmania, and at the Trinidad Head Observatory, California. From the same flasks, measurements are made by Ben R. Miller at the Scripps Institution of Oceanography for the trace gases methyl chloride (CH3Cl) and methyl bromide (CH3Br). Also, in-situ measurements of 'AGAGE' trace gases are made at the two collection sites simultaneously to the collection of these flask samples. The goal of this program is the monitoring of these trace gases to study their atmospheric trends and their global budgets. Also the SF6 atmospheric record needs to be known in order to use this gas as a time-dependent transient tracer in marine and limnological studies.

Below is a figure showing the atmospheric SF6 trend at the two sites. The figure can also be downloaded as: [PDF] or as [PS] file. This project is ongoing. M. K. Vollmer, B. R. Miller, R. F. Weiss, preliminary data, 2004. Sample are collected by Laurie Porter for Cape Grim and by Wendy Snible and now Randy Dickau for Trinidad Head.

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