1. Climate and Global Dynamics Division; National Center for Atmospheric Research; Boulder Colorado USA
2. Department of Geological Sciences; University of Texas at Austin; Austin Texas USA
3. Cooperative Institute for Research in Environmental Sciences; University of Colorado; Boulder Colorado USA
4. Department of Atmospheric Science; Colorado State University; Fort Collins Colorado USA
5. Institute for Atmospheric and Climate Sciences; ETH Zurich; Zurich Switzerland
6. NASA Earth Observatory; Goddard Space Flight Center; Greenbelt Maryland USA
7. Department of Earth and Atmospheric Sciences; Georgia Institute of Technology; Atlanta Georgia USA