1. Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, and NOAA/OAR/ESRL/Global Systems Division, Boulder, Colorado
2. Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, and NOAA/OAR/ESRL/Global Systems Division, Boulder, Colorado, and NASA Goddard Institute for Space Studies, New York, New York
3. NOAA/OAR/ESRL/Global Systems Division, Boulder, Colorado