I earned a Bachelor’s degree (1975) from Prescott College, Prescott, Arizona and Masters (1978) and Ph.D. (1981) degrees from the University of California, Davis. I completed Post-doctoral training (1983) at the University of California before joining the faculty of Texas A&M University (1983-1989) where I also held an appointment in the Texas Agricultural Experiment Station. I joined the National Park Service as a research scientist at Indiana Dunes National Park (1989-1991) before being offered the Climate Change Research Coordinator position (1991) at Glacier National Park, Montana, as part of the nationwide United States Global Change Research Program. This position in the Department of Interior was moved briefly to the National Biological Service (1993-1996) before being transferred to the United States Geological Survey (USGS). In 2018 I received the Shoemaker Lifetime Achievement Award for Science Communication from the USGS. I served in the USGS until my retirement in 2020, continuing as Scientist Emeritus post-retirement.
At Glacier National Park, I helped develop a national climate change research program within the National Park Service, coordinating with other Biogeographical Area Coordinators across the breadth of national parks from Florida to Alaska. I built a research program centered on Glacier Park as a representative mountain ecosystem, engaging faculty and scientists from Montana universities and across the U.S. To address climate change impacts on mountain systems, this research program involved diverse disciplines, including ecosystem modelling, hydrology, paleoecology, UV-B effects on amphibians, alpine vegetation dynamics and the physics of snow avalanches. The alpine glaciers of Glacier Park became an early focus of climate change research because they were expected to be sensitive indicators of changing temperatures and precipitation (e.g., Oerlemans, 1994). I and others established aerial photography surveys of glaciers in 1993, began a repeat photography program in 1997, used GIS and emerging satellite platform remote sensing technologies to map glaciers in late 1990s (Key et al., 2002), and constructed a geospatial glacial melt model (Hall and Fagre, 2003). Global Positioning System (GPS) technologies were used to map glacier ice margins and on-ice studies began in 2003. In conjunction with geology faculty at University of Montana, a mass balance monitoring program of Sperry Glacier was established in 2005 and was eventually joined in 2013 to the USGS Benchmark Glacier program, begun in 1957, and the World Glacier Monitoring Service based in Switzerland. In recent years, automated climate stations and ice-penetrating radar have been deployed on the glaciers, and airborne LiDAR and classified satellite data have improved glacier mapping.