1. Department of Atmospheric Sciences University of Washington Seattle WA USA
2. Now at Laboratory of Atmospheric Chemistry Paul Scherrer Institute Villigen Switzerland
3. Chemical Sciences Division, Earth System Research Laboratory National Oceanic and Atmospheric Administration Boulder CO USA
4. Cooperative Institute for Research in Environmental Science University of Colorado Boulder Boulder CO USA
5. Department of Chemistry University of Colorado Boulder Boulder CO USA
6. Department of Chemistry University of California Berkeley CA USA
7. Atmospheric Chemistry Observations and Modeling Laboratory National Center for Atmospheric Research Boulder CO USA
8. NASA Langley Research Center Hampton VA USA
9. Atmospheric Chemistry and Dynamics Laboratory NASA Goddard Space Flight Center Greenbelt MD USA
10. Joint Center for Earth Systems Technology University of Maryland, Baltimore County Catonsville MD USA
11. Department of Atmospheric Science Colorado State University Fort Collins CO USA
12. School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA USA