1. Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195, United States
2. Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
3. Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
4. Cooperative Institute for Research in Environmental Sciences and Department of Chemistry, University of Colorado, Boulder, Boulder, Colorado 80309, United States
5. Department of Applied Physics, University of Eastern Finland, 70211 Kuopio, Finland
6. Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California 94720, United States
7. Office of Research and Development, Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States