DOI: 10.5066/p9h2mm1m
title: Small Unoccupied Aircraft System Imagery and Associated Data used for Discharge Measurement at Eight Locations Across the United States in 2019 and 2020

description: A series of field measurements of surface water velocity derived from video collected by small unoccupied aircraft systems (sUAS) was conducted at eight locations in Arizona, New Mexico, California, and Maine, USA during the summers of 2019 and 2020. The measurements are utilized to compute surface velocity and discharge using the Large-Scale Particle Image Velocimetry (LSPIV) image velocimetry method. This data release includes the original video and subsequent processing results of this analysis. Data are grouped into sections (child items) based on the data type and purpose: Ancillary Scripts: this child item contains Mathworks MATLAB script files which reproduce the processing steps for each dataset. Additional scripts which reshape the data into the form it is in this data release, as well as generate the plots in the “Particle Image Velocimetry Images” child item are included. Calibration Images: this child item contains images with labeled ground control points and associated pixel coordinate locations for each dataset. The images can be used to calibrate image velocimetry results into real world units (meters, for example). Discharge Measurements: this child item contains the raw acoustic Doppler velocity profiler (ADCP) and acoustic Doppler velocimeter (ADV) measurements collected by U.S. Geological Survey hydrographers at each site for the purpose of validating LSPIV results. Masks: this child item contains simple text files representing processing masks (areas where LSPIV are not processed) used by the PIVLab software for some of the sites. Masks are used to ensure non-water objects such as trees or banks are omitted from analysis. Particle Image Velocimetry Images: this child item contains the image frames extracted from the videos collected for each site by sUAS. Three sets of images are included for each site: (i) original, unmodified frames, (ii) motion stabilized frames, and (iii) motion stabilized frames with the background subtracted. Particle Image Velocimetry Results: this child item contains Mathworks MATLAB mat-files with self-describing metadata containing the processed LSPIV results. A sub-child item entitled, "Particle Image Velocimetry Images", contains the output from the script "CreatePlots.m" (see Ancillary Scripts child item) using the LSPIV results. Videos: this child item contains the raw videos captured by sUAS at each site which are used for analyses. Each Field Site is abbreviated in various files in this data release. File and folder names are used to quickly identify which site a particular file or dataset represents. The following abbreviations are used: WMD: Wellton-Mohawk Main Outlet Drain near Yuma, Arizona, USA SMC: Sile Main Canal (at head) at Cochiti, New Mexico, USA RMC: Reservation Main Canal near Yuma, Arizona, USA GLR: Gila River near Dome, Arizona, USA CMC: Cochiti East Side Main Channel, near Cochiti, New Mexico, USA CCC: Coachella Canal above All-American Canal Diversion, California, USA AFR: Agua Fria River, near Rock Springs, Arizona, USA ACR: Androscoggin River, Auburn, Maine, USA Software Requirements ?To execute the scripts included in the "Ancillary Scripts" child item, users will need to have the following software: Mathworks MATLAB. Users can install a free trial version of MATLAB by going to the Mathworks site (https://matlab.mathworks.com/). The scripts in this child item have a dependency on the PIVLab open source souftware, version 2.55 or newer. PIVLab can be downloaded from this website: https://pivlab.blogspot.com/