A HIGH-RESOLUTION DEM TIMESERIES TO MEASURE GLACIER MASS BALANCE, DYNAMICS, AND VARIABILITY AT MOUNT BAKER, WA USA
We present a preliminary 2013-2014 timeseries of high-resolution digital elevation models (DEMs) derived from oblique aerial Structure from Motion (SfM) surveys, small UAV SfM surveys, ground-based SfM surveys, and WorldView along-track stereo satellite imagery. The baseline DEM for Mount Baker (9/10/13) was generated from 506 oblique photos acquired from a single-engine airplane with a handheld 36 Megapixel camera. Automated SfM software was used to produce a 1.3 meter per pixel (m/px) DEM and 0.3 m/px orthomosaic, both with areal coverage of ~105 km2. Standard error of ~0.5 m and RMSE of ~2.7 m are estimated from comparisons with 13 USGS GPS sites. Photographs acquired by compact cameras on small, low altitude, UAV platforms allow us to produce DEM and orthoimage products with cm-scale resolution over ~1-5 km2. Finally, we use WorldView satellite stereo imagery to generate ~2.0 m/px DEMs over ~250-300 km2. Cloud-free stereopairs are available from 9/11/13, 9/13/13 and 5/14/14, with additional acquisitions planned for 9/1/14-10/15/14.
We will use this DEM timeseries to produce seasonal and interannual volume/mass change estimates for Mount Baker. Future comparisons with in situ measurements and similar DEM timeseries throughout the Cascades will offer new insights for regional mass balance estimates, while also establishing baselines for other dynamic geologic processes (e.g., volcanic deformation, mass wasting).