| Summary: | Airborne photogrammetric data were acquired two times in 2015 (April 23 and July 5), three times in 2016 (April 19, July 11, and August 5), and three times in 2017 (April 28, June 27, and September 3). These data were used to create digital elevation models (DEMs) with postings of 50 cm provided in NAD83(2011) (North American Datum) NAVD88 (North American Vertical Datum) Geoid 12B (unless otherwise specified). When conditions permitted (April 23, 2015; July 5, 2015; April 19, 2016; April 28, 2017), the entire Carnivore Creek watershed was acquired. On all other dates, only the eastern side of the valley, where the catchment glaciers are located, was captured. These data were acquired using a Nikon DSLR (digital single-lens reflex) attached to a survey grade GNSS (Global Navigation Satellite System) on board a manned aircraft, providing photo-center position to 10 cm or better and thus eliminating the need for ground control. These DEMs were used to create difference DEMs that can be used to measure snowpack thickness throughout the entire watershed as well as glacier surface elevation change.
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