A high-resolution DEM record for Mt. Rainier and CONUS glaciers: geodetic mass balance, glacier dynamics, snow depth, and natural hazards


Mountain glaciers represent only ~1% of the total freshwater on Earth, yet due to increasing mass imbalance, they are responsible for ~30% (~1 mm/yr) of present-day sea level rise. On a regional scale, they are indicators of climate change and serve as important seasonal/long-term hydrologic reservoirs. We generated ~500 high-resolution digital elevation models (DEMs) from sub-meter commercial stereo imagery (DigitalGlobe WorldView/GeoEye constellation) acquired over glaciers in the Contiguous US (CONUS) from 2008-present. We produced a ~2015 DEM mosaic and estimated ~5-10 year and long-term (~30-60 year) geodetic mass balance for ~700 glaciers larger than 0.1 km2 using airborne LiDAR data from ~2008-2010 and National Elevation Dataset (NED) data with source dates of ~1950-1980. These results provide new information about the spatial distribution and evolution of CONUS glacier mass balance, with greatest loss rates observed for high-latitude, low-elevation glaciers. We also generated monthly to interannual DEM time series for high-priority sites, including >40 stereo DEMs from 2014-2016 for Mt. Rainier. This record offers new details about seasonal snow accumulation and redistribution on Mt. Rainier, including high-elevation areas near the summit with limited in situ observations. We generated high-resolution velocity maps and document dynamic surface elevation anomalies (+/-20-30 m) for a subset of Mt. Rainier’s fast-flowing glaciers. These efforts will provide basin-scale estimates of snow water equivalent (SWE) and snow/ice melt runoff contributions for downstream water resource applications (e.g., hydropower, irrigation, municipal use). Finally, these observations also document dynamic landscape evolution (e.g., landslides, sediment redistribution) that can be used for both hazard assessment and rapid response to natural disasters (e.g., outburst floods).

Seattle, WA