1. Chemical Sciences Division, Earth System Research Laboratory NOAA Boulder CO USA
2. Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder Boulder CO USA
3. Department of Chemistry University of Colorado Boulder Boulder CO USA
4. Department of Atmospheric Sciences University of Washington Seattle WA USA
5. Earth and Atmospheric Sciences Department Georgia Institute of Technology Atlanta GA USA
6. Earth Observing Laboratory NCAR Boulder CO USA
7. Atmospheric Chemistry Observations & Modeling Laboratory NCAR Boulder CO USA
8. Institute for the Study of Earth, Oceans, and Space University of New Hampshire Durham NH USA
9. Department of Chemistry University of California Berkeley Berkeley CA USA