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Fusing Digital Elevation Datasets to Create a Best Currently Available Composite DEM for ABoVE
Patrick
Burns, Northern Arizona University, pb463@nau.edu
(Presenter)
Digital elevation models (DEMs) are necessary for a variety of Earth Science applications, including image orthorectification and topographic correction, as well as hydrologic and vegetation modeling. Working at very large scales, such as the entire NASA ABoVE domain, it is often beneficial to perform analyses using contiguous (gap-free) DEMs that have an associated vertical accuracy metric. Currently no single, publicly-available elevation dataset covers the entire ABoVE study domain. For this reason we created a best currently available composite using the following publicly-available elevation datasets, ranked in order of overall quality: airborne ifsar (Alaska only), ArcticDEM, ALOS World 3D, Shuttle Radar Topography Mission DEM, Canada DEM, and ASTER Global Digital Elevation Model. The input datasets have variable spatial resolution and temporal acquisition dates, as well as horizontal and vertical accuracy. Furthermore, the input datasets are referenced from different horizontal and vertical datums (not to mention reference frame epochs), and also span the USA-Canada border. The input datasets are first harmonized to a common reference frame (same horizontal and vertical datums: WGS84, EGM2008) and then composited as one ESRI master mosaic dataset on the ABoVE Science Cloud. This master mosaic dataset allows users flexibility when exporting their sub-project-specific composites. For example, a user could filter the master mosaic dataset to only include DEMs acquired between 2010 and 2015 with a vertical accuracy less than 10m (LE90). The initial version of this ABoVE best currently available elevation composite (v1) will be tiled based on the ABoVE grid system at 10m spatial resolution and include all datasets made publicly available through the end of 2017. Vertical accuracy metrics are tied to individual input DEMs (where available) and overall vertical accuracy of the composite is assessed using airborne lidar and airport runway elevations. Associated Project(s): Poster Location ID: 93 Session Assigned: Vegetation Dynamics and Distribution
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