Thermal image indicates water temperature, with yellow and purple

igure 1. Thermal image indicates water temperature, where warmer temperatures are represented as yellow and cooler temperatures as purple. The image presents a groundwater seep at the edge of a stream, where groundwater discharge (yellow) is flowing over rocky/sand substrate and mixing with the colder (purple) stream. Temperature is in degrees Celsius. Image is of an area about one-half meter wide. Image courtesy USGS Leetown Science Center.