High-resolution mapping of river-hydrothermal water mixing: Yellowstone National Park
Abstract:Thermal mixing in rivers is a common geophysical phenomenon that controls myriad processes, from aquatic ecological functions to stream and groundwater biogeochemistry. We present high-resolution remotely-sensed temperature distributions of thermal plumes discharging into rivers collected from Yellowstone National Park. Airborne (4 m pixel size) and ground-based (centimetre or better spatial resolution) images corroborate the presence of these mixing zones. They illustrate that thermal discharges in rivers may not be well-mixed with the bulk flow even after traversing distances corresponding to several stream widths. This allows for large thermal gradients (>30°C) to persist between the thermal discharge and the bulk flow. The plumes may have pronounced internal temperature gradients that vary in space and time. The images illustrate the potential of portable high-resolution sensors not only for acquiring observations needed for fundamental understanding of non-isothermal mixing processes but also for providing temperature distributions necessary for understanding many thermally-mediated processes.
Document Type: Research Article
Affiliations: 1: Department of Geological Sciences, University of Texas at Austin, Austin, TX, USA 2: Biological and Irrigation Engineering Department, Utah State University, Remote Sensing Services Laboratory, Logan, UT, USA 3: Yellowstone Center for Resources, Yellowstone National Park, WY, USA
Publication date: May 1, 2011