1. Department of Atmospheric Sciences University of Washington Seattle WA USA
2. Now at Tofwerk AG Thun Switzerland
3. Earth Observing Laboratory National Corporation for Atmospheric Research 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. Chemical Sciences Division NOAA Earth System Research Laboratory Boulder CO USA
7. Now at California Air Resources Board Sacramento CA USA
8. Now at the Department of Physics and Atmospheric Science Dalhousie University Halifax Nova Scotia Canada