[1] Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA
[2] Univ Manchester, Sch Earth Atmospher & Environm Sci, Natl Ctr Atmospher Sci, Manchester, Lancs, England
[3] Karlsruhe GmbH IMK IFU, Forschungszentrum, Inst Meteorol & Climate Res, Karlsruhe, Germany
[4] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA
[5] Univ Nacl Autonoma Mexico, Ctr Ciencias Atmosfera, Mexico City 04510, DF, Mexico