[1] Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA
[2] NASA, Langley Res Ctr, Hampton, VA 23681 USA
[3] Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA
[4] NOAA, Aeron Lab, Boulder, CO 80303 USA
[5] Univ Rhode Isl, Grad Sch Oceanog, Ctr Atmospher Chem Studies, Narragansett, RI 02882 USA
[6] Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03820 USA