1. Aeronomy Laboratory,
2. Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA.
3. School of the Environment, University of Leeds, Leeds LS2 9JT, UK.
4. Rutherford Appleton Laboratory, Chilton, Didcot, OX 11 OQX, UK.
5. Universidad Nacional Autónoma de México, Centro de Ciencias de la Atmósfera, Ciudad Universitaria, 04510 Mexico DF, Mexico.
6. National Center for Atmospheric Research, Boulder, CO 80307, USA.
7. Division of Geology and Planetary Sciences,
8. Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA 91125, USA.
9. Laboratorium für Atmosphärenphysik, Eidgenössiche Technische Hochschule Zürich, CH-8093 Zürich, Switzerland.
10. NASA Jet Propulsion Laboratory, Pasadena, CA 91109, USA.
11. NASA Ames Research Center, Moffett Field, CA 94035, USA.
12. Climate Monitoring and Diagnostics Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA.
13. Bay Area Environmental Research Institute, San Francisco, CA 94122, USA.
14. Department of Engineering, University of Denver, Denver, CO 80208, USA.
15. Institute of Environmental Physics, University of Bremen, D-28334 Bremen, Germany.