Publication Date:
2019
Description:
Abstract
The utility of differentially mapping snow depth to assess snow water resources at the watershed scale has been demonstrated using snow free and snow on lidar surface elevations. On more limited spatial and temporal scales, the same principle has been successfully applied with the relatively new photogrammetric technique Structure from Motion (SfM). Given the low cost of cameras relative to lidar technology early studies are promising, yet it is well known that reconstructing elevations over bright snow surfaces in complex terrain has been a limitation for traditional photogrammetric methods. Therefore, before progressing to snow depth, it is worthwhile to constrain how well snow surface elevations are mapped with SfM. The lidar based Airborne Snow Observatory, which also has an RGB camera, provides a unique opportunity to assess SfM against coincidentally collected lidar. Here, we present a lidar‐SfM snow surface elevation comparison from the February 21st, 2017 flight, which took place in Senator Beck Basin, San Juan Mountains, CO, during the NASA SnowEx campaign (Year 1). After co‐registration of the two surface models the Normalized Median Absolute Deviation (NMAD) was 0.17 m with a mean relative elevation difference of 0.014 m at identical spatial resolution of 1m. The digital surface model (DSM) was created without the use of ground control points (GCPs), and shows a promising potential to apply SfM for watershed scale surface elevation and snow depth mapping, and warrants further investigation of SfM as a supplement or alternative to lidar.
Print ISSN:
0043-1397
Electronic ISSN:
1944-7973
Topics:
Architecture, Civil Engineering, Surveying
,
Geography
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