1. Atmospheric, Oceanic and Space Sciences; University of Michigan; Ann Arbor Michigan USA
2. Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
3. Earth and Environmental Sciences; Los Alamos National Lab; Los Alamos New Mexico USA
4. Now at Pacific Northwest National Laboratory; Atmospheric Chemistry and Global Change Division; Richland Washington USA
5. Department of Earth Science and Engineering; California Institute of Technology; Pasadena California USA