Low-altitude (70 m above ground level) aerial images were collected over 5 areas of interest within the northern portion of Assateague Island National Seashore (ASIS) in mid-October, 2022. These images were collected to generate photogrammetric products (e.g. digital surface model (DSM), reflectance orthomosaic) for five areas of interest along the northern portion of the island to support science and data needs of National Park managers attempting to locate invasive Phragmites australis expansion. A DJI Matrice 600 uncrewed aircraft system (UAS) was equipped with a MicaSense Altum-PT multispectral camera and a Ricoh GRII true-color RGB camera to collect images simultaneously with sufficient overlap for photogrammetric processing. Ground control points (GCPs), black and white targets visible in the imagery, were deployed prior to imagery collection to improve the horizontal and vertical accuracy of the DEM, orthomosaic, and reflectance products. GCP locations are recorded using wifi-enabled or survey-collected Real Time Kinematic Global Position System (RTK-GPS) information. Ground-reference vegetation and spectral profile data were collected to aid in imagery analysis, including training and validation for machine learning classification techniques. This data release includes the following: (1) original images from the Ricoh GRII and MicaSense Altum-PT cameras as well as (2) the GCPs needed to produce accurate photogrammetry products, (3) physical and GPS data from the vegetation survey, (4) spectral reflectance profiles and GPS data, and (5) photogrammetric products, including DSMs from both imagery datasets, a true-color orthomosaic and a reflectance orthomosaic.
|Title||Topographic and multispectral reflectance products, aerial imagery, spectral reflectance profiles, vegetation surveys, and associated GPS data collected during uncrewed aircraft system (UAS) operations: Assateague Island National Seashore, Maryland, Octob|
|Authors||Jennifer M Cramer, Alexandra D Evans, Sandra M Brosnahan, Jin-Si R Over, Seth Ackerman, Erika Lentz, Bill Hulslander|
|Product Type||Data Release|
|Record Source||USGS Digital Object Identifier Catalog|
|USGS Organization||Woods Hole Coastal and Marine Science Center|