1. Fundamental Science Division, Pacific Northwest National L aboratory, PO Box 999, Richland, WA 99352, USA;
2. East Giant Science and Technology Inc., 45 Rock Fernway, Toronto, ON, M2J 4N3, Canada;
3. Climate and Atmospheric Science Directorate of Environment Canada, 4905 Dufferin St., Toronto, ON, M3H 5T4, Canada;
4. Atmospheric Science Program, Physics Department, Dalhousie University, Halifax, NS, Canada;
5. Nicholas School of the Environment, Duke University, Durham, NC, USA;
6. (IMAU) Utrecht University, Utrecht, The Netherlands;
7. European Commission Environment Institute, Ispra, Italy;
8. Department Experimental Physics, University College, Dublin, Ireland;
9. Environmental Science Department, Brookhaven National Laboratory, Upton, NY, USA;
10. Laboratoire de Glaciologie et Geophysique de l’Environnement, Grenoble, France;
11. Centre for Atmospheric Science, Department of Chemistry, University of Cambridge, UK;
12. University of Miami, Miami, FL, USA;
13. Atmospheric Sciences Research Center, State University of New York, Albany, NY, USA;
14. Atmospheric Science Division, Lawrence Livermore National Laboratory, Livermore, CA, USA;
15. NASA Goddard Space Flight Center, Greenbelt, MD, USA;
16. National Environmental Research Institute, Roskilde, Denmark;
17. Max Planck Institute forMeteorology, Hamburg, Germany;
18. Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands;
19. Department of Meteorology, Stockholm University, S-106 91 Stockholm, Sweden;
20. Goddard Institute for Space Studies, Department of Geology and Geophysics, New Haven, CT, USA;
21. National Center for Atmospheric Research (NCAR), Boulder, CO, USA