Airborne Thermal Infrared and True-color Imagery and Longitudinal Profiles of Stream Temperatures, McKenzie River Basin, Oregon, September 1999

This dataset includes high-resolution thermal infrared (TIR) and true-color images collected from crewed aircraft and a point shapefile and corresponding comma-delimited tabular data representing the longitudinal spatial patterns of water surface temperature in the surveyed streams in the McKenzie River basin, Oregon. The USDA Forest Service, McKenzie River Ranger District contracted with Oregon State University (Forest Science Department and Department of Fisheries and Wildlife) and Snowy Butte Helicopters of Medford, Oregon for the aerial surveys. The TIR and true-color images were collected with an AGEMA Infrared Systems, Thermovision 1000 forward-looking infrared (FLIR) imager and a video camera on a gyro-stabilized mount attached to a helicopter. Surveys of 61.2 kilometers (km) in 3 streams within the McKenzie River basin were conducted on September 3, 1999, in the afternoon (15:00-16:00 PDT) under warm seasonal conditions. The air temperature during the survey flight at the Trout Creek, Oregon Remote Automated Weather Station (RAWS) (732 meters [m] elevation; https://raws.dri.edu/cgi-bin/rawMAIN.pl?orOTRO accessed July 3, 2025) ranged from 27 to 28 degrees Celsius (C). Individual TIR image frames and true-color image frames are provided in tag image file (TIF) format with approximate ground resolutions ranging from 0.25 to 0.50 meters (m). The TIR rasters contain corrected radiant surface temperatures in degrees C rounded to the nearest integer to create an unsigned pixel type. The radiant temperatures derived from the TIR rasters were evaluated for accuracy with kinetic temperatures from 6 in-stream data loggers positioned where water velocity was assumed sufficient for vertical mixing; the TIR imagery met the contract-specified accuracy of ±0.5°C difference between the TIR image and the in-stream data logger. The longitudinal stream temperatures are provided in geospatial format (i.e., point shapefiles [.shp] modified in ESRI ArcGIS Pro 3.4) and in comma-separated value (CSV) tabular format. The shapefile point features spaced along the survey flight paths approximately every 15-75 m were linearly referenced with respect to their distance upstream in river km using ARC/INFO geographic information system (GIS) software based on “routed” 1:100,000-scale hydrography from the U.S. Environmental Protection Agency (EPA) River Reach File Version 3.0 hydrographic database of surface waters (https://archive.epa.gov/esd/archive-nerl-esd1/web/html/nvgeo_gis10_rf3_…). Stream temperature statistics in the shapefiles and tabular data were derived by manually selecting and sampling pure-water pixels in each TIR image (ARC/INFO GRID format) with a semi-automated Avenue script in ESRI ArcView GIS 3.1 along the main channel of each stream reach.