Ground-based thermography of fluvial systems at low and high discharge reveals potential complex thermal heterogeneity driven by flow variation and bioroughness
Article first published online: 31 JAN 2008
Copyright © 2008 John Wiley & Sons, Ltd.
Special Issue: River and Stream Temperature: Dynamics, Processes, Models and Implications
Volume 22, Issue 7, pages 980–986, 30 March 2008
How to Cite
Cardenas, M. B., Harvey, J. W., Packman, A. I. and Scott, D. T. (2008), Ground-based thermography of fluvial systems at low and high discharge reveals potential complex thermal heterogeneity driven by flow variation and bioroughness. Hydrol. Process., 22: 980–986. doi: 10.1002/hyp.6932
- Issue published online: 6 MAR 2008
- Article first published online: 31 JAN 2008
- Manuscript Accepted: 15 OCT 2007
- Manuscript Received: 8 JUN 2007
- U.S. Geological Survey's National Research Program and US National Science Foundation. Grant Number: EAR-0408744
Temperature is a primary physical and biogeochemical variable in aquatic systems. Field-based measurement of temperature at discrete sampling points has revealed temperature variability in fluvial systems, but traditional techniques do not readily allow for synoptic sampling schemes that can address temperature-related questions with broad, yet detailed, coverage. We present results of thermal infrared imaging at different stream discharge (base flow and peak flood) conditions using a handheld IR camera. Remotely sensed temperatures compare well with those measured with a digital thermometer. The thermal images show that periphyton, wood, and sandbars induce significant thermal heterogeneity during low stages. Moreover, the images indicate temperature variability within the periphyton community and within the partially submerged bars. The thermal heterogeneity was diminished during flood inundation, when the areas of more slowly moving water to the side of the stream differed in their temperature. The results have consequences for thermally sensitive hydroecological processes and implications for models of those processes, especially those that assume an effective stream temperature. Copyright © 2008 John Wiley & Sons, Ltd.