Satellite images used to test a sundial method for inferring image acquisition time from shadow orientation

This data release provides satellite images used to test a method for inferring image acquisition time from shadow orientation. For many applications, such as linking remotely sensed data to streamflow recorded at a gaging station, knowing the time an image is acquired is important, but such metadata often is not available. The sundial method is a simple means of inferring image acquisition time from shadow orientation. Images with known acquisition times are used to test the approach.
The file SundialDataRelease.csv contains image metadata, shadow measurements, and inferred image acquisition times based on the sundial method. The difference between the known acquisition times of the satellite images and those inferred via the sundial technique is used to assess the accuracy of the method. Please refer to the entity and attribute section of the metadata for further detail regarding this file.
The file SundialImages.zip contains 16 WorldView satellite images with known acquisition times that were used to test the sundial method. Each image is provided in a GeoTIFF format that includes embedded spatial referencing information.
This project is a collaboration between the University of Idaho Center for Ecohydraulics Research and the USGS supported by the USGS Next Generation Water Observing System External Research and Development Program.

Users are advised to thoroughly read the metadata file associated with this data release to understand the appropriate use and limitations of the data and code provided herein.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. MAXAR retains the copyright on all the images: "© 2024 MAXAR".