Byrd Glacier Historical Air Photo DEM 10m v1
Description
This dataset is comprised of two DEMs (10 m spatial resolution) that were generated from aerial images collected in December 1978 and January 1979 over Byrd Glacier, East Antarctica. The air photos were initially manually processed in 1980 (Brecher, 1982) and then mislaid for 36 years until eventually found in the basement of the USGS Reston Branch Library in 2016. The images were digitized by the USGS EROS Center at 1,000 dpi and are available from https://earthexplorer.usgs.gov/. The exact images used in the processing may be found in the Supplemental Information from Child et al., (submitted). The elevations were estimated using opensource structure-from-motion (SfM) photogrammetry software called MicMac (https://github.com/micmacIGN) with ground control manually extracted from the Regional Elevation Model of Antarctica (http://data.pgc.umn.edu/elev/dem/setsm/REMA/geocell/v1.0/2m/). The DEMs are projected horizontally to WGS84 Polar Stereographic and vertically to the WGS84 ellipsoid. Both DEMs have been registered to in situ GPS (https://www.usap-dc.org/view/project/p0000319) from exposed bedrock, but only three GPS site data are available. The vertical error of the GPS data is ~2-5 cm. It is recommended that a more spatially expansive registration should be carried out first before any analysis be conducted. The root mean square error of the December 1978 DEM after registration is 0.50 m and 2.30 m for the January 1979. Brecher, H.H., 1982. Photographic determination of surface velocities and elevations on Byrd Glacier. Antarctic Journal 17, 79–81.