1. Department of Geology and Geography, West Virginia University, 98 Beechurst Avenue, Morgantown, WV 26501, USA.
2. School of Geography and Development and Laboratory of Tree-Ring Research, University of Arizona, AZ 85721, USA.
3. Department of Statistics, West Virginia University, Morgantown, WV 26506, USA.
4. Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA.
5. NASA Goddard Institute for Space Studies, New York, NY 10025, USA.
6. Department of Forestry, National University of Mongolia, Ulaanbaatar, Mongolia.
7. Harvard Forest, Harvard University, Petersham, MA 01366, USA.
8. School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849, USA.