The U.S. Geological Survey contracted with Juniper Unmanned to conduct field tests of the Infrared Cameras Inc. (ICI) Mirage camera on the Blue River just upstream of its confluence with the Colorado River near Kremmling, Colorado, on October 18, 2018. The objective of this project was to assess the potential to infer surface flow velocities in rivers by applying a particle image velocimetry (PIV) algorithm to aerial thermal infrared image time series collected from an unmanned aircraft system (UAS). The ICI Mirage (3-5 µm thermal IR) and a Sony DSC QX-30 (natural color) cameras were mounted on a Gremsy H7 gimbal, integrated with the ICI sensor control module (SCM), and mounted to a DJI Matrice 600 Pro UAS owned and operated by Juniper Unmanned. The SCM includes a Micro SD card to store the image data. At the instant each thermal or natural color image was acquired, the time, position, elevation, and orientation with respect to magnetic north was written to the image file as part of the EXIF header.
On October 18, 2018, operations began at civil twilight, approximately 6:50 AM MDT, with the first flights occurring about the same time (per EXIF information). The sky was cloudy, and no wind was apparent at the field site. The temperature of the air was approximately 27° Fahrenheit (-2.8° C) and no wind was measured at the Mc Elroy airfield (K20V) at 7AM. This data release includes images from hovering collections at two locations (waypoints) in the study area, each approximately 1 minute in duration. The waypoints were loaded in the UgCS software. At one of these waypoints the entire width of the river could not be captured at the maximum flight altitude permitted (~400 ft Above Ground Level) so the images do not include both banks of the channel.
The data are provided as zip files with image sequences, one for each of the two cross-sections on the Blue River. The U.S. Geological Survey has an ongoing research interest in developing and testing innovative technologies for remote sensing of surface flow velocities as one component of an integrated approach to non-contact measurement of river discharge.