1. Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, Davis, CA 95616, USA.
2. Department of Geosciences, and Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA 16802, USA.
3. Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark.
4. School of Geography and the Environment, University of Oxford, Oxford OX1 3QY, UK.
5. Arctic Centre, University of Lapland, Box 122, FI-96101 Rovaniemi, Finland.
6. Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80303, USA.
7. Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022, USA.
8. Neukom Institute for Computational Science, Institute of Arctic Studies, and Environmental Studies Program, Dartmouth College, Hanover, NH 03755, USA.
9. Polar Science Center, Applied Physics Laboratory, University of Washington, 1013 NE 40th Street, Seattle, WA 98105, USA.
10. Department of Meteorology and Atmospheric Science and Department of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA.
11. Department of Ecology and Environmental Science, Umeå University, S-901 87 Umeå, Sweden.
12. University College London, Bloomsbury, London, UK.
13. National Snow and Ice Data Center, Boulder, CO 80303, USA.
14. Chair, U.S. Arctic Research Commission, 420 L Street, Suite 315 Anchorage, AK 99501, USA.
15. Chair, U.S. Artic Research Commission, 4350 N. Fairfax Drive, Suite 510, Arlington, VA 22203, USA.
16. Belfer Center for Science and International Affairs John F. Kennedy School of Government, Harvard University, Cambridge, MA 02138, USA.
17. Institute of Arctic Studies, and Environmental Studies Program, Dartmouth College, Hanover, NH 03755, USA.
18. Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, WA 98195, USA.
19. National Oceanic and Atmospheric Administration Pacific Marine Environmental Laboratory, Seattle, WA 98115, USA.