1. National Science Foundation Postdoctoral Fellow hosted at U.S. Geological Survey Eastern Geographic Science Center 12201 Sunrise Valley Drive, MSN 521 Reston VA 20192 USA
2. U.S. Geological Survey Eastern Geographic Science Center 12201 Sunrise Valley Drive, MSN 521 Reston VA 20192 USA
3. U.S. Geological Survey National Research Program 12201 Sunrise Valley Drive, MSN 430 Reston VA 20192 USA