1. Center for Limnology, University of Wisconsin–Madison, Madison, WI 53706, USA.
2. U.S. Geological Survey, Water Resources Division, 8505 Research Way, Middleton, WI 53562, USA.
3. Department of Forestry, Virginia Polytechnic Institute and State University, 319 Cheatham Hall, Blacksburg, VA 24061, USA.
4. Department of Environmental Physics, Swiss Federal Institute of Environmental Science and Technology, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland.
5. Department of Geography, Rissho University 4-2-16 Osaki, Shinagawa-Ku, Tokyo 141, Japan.
6. Great Lakes Ecosystem Research Laboratory, National Oceanic and Atmospheric Agency, 2205 Commonwealth Boulevard, Ann Arbor, MI 48105–1593, USA.
7. World Data Center for Glaciology, University of Colorado at Boulder, Boulder, CO 80309–0449, USA.
8. College of Arts and Sciences, Metropolitan State University, 700 East 7 Street, St. Paul, MN 55106, USA.
9. Finnish Environment Institute, Post Office Box 140, FIN-00251 Helsinki, Finland.
10. Limnological Institute, Post Office Box 4199, Irkutsk 664033, Russia.
11. National Water Research Institute, Environment Canada, 11 Innovation Boulevard, Saskatoon, SK S7N 3H5, Canada.
12. Department of Biological Science, State University of New York at Buffalo, Buffalo, NY 14260, USA.
13. State Hydrological Institute, 23 Second Line, St. Petersburg 199053, Russia.