EOMF-14. What can you learn from measurements of a trace gas?

Abstract
The Halocarbons and other Atmospheric Trace Species division of the NOAA Global Monitoring Lab measures a variety of gases present in the atmosphere at concentrations as small as parts per trillion. Our focus is on greenhouse gases other than carbon dioxide and halogenated compounds that can destroy stratospheric ozone, as well as various hydrocarbons. We currently measure concentrations in flask samples of air collected from sites around the world, in-situ at continuously operating instruments at a subset of those sites, and on aircraft missions. My focus is on the flask sampling program. For this program, samples are collected roughly weekly at sites in Colorado, Wisconsin, Massachusetts, Alaska, American Samoa, Hawai’i, California, Canada, Ireland, Israel, South Korea, Australia, Greenland, and Antarctica and then shipped to our lab in Boulder for analysis on three instruments. The data produced are subject to rigorous quality control, and after some time, are made available on our website. New developments include a recently built gas chromatograph electron capture detection system for analyzing flask samples, and hopefully soon starting to collect samples at a new site in Barbados. What kinds of questions can you ask using long-term records of trace-gas concentrations?