1. Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523, USA;
2. Department of Environmental Sciences, Cook College, Rutgers University, New Brunswick, NJ 08903, USA;
3. Atmospheric and Terrestrial Processes, CSIRO Centre for Environmental Mechanics, GPO Box 821, Canberra, ACT 2601, Australia;
4. DLO Winand Staring Centre, PO Box 125, 6700 C Wageningen, The Netherlands;
5. Department of Atmospheric Science, PAS Building #81, The University of Arizona, Tucson, AZ 85721, USA;
6. School of Environmental Sciences and Management, University of California, Santa Barbara, CA 93106‐5131, USA