A distributed stream temperature model using high resolution temperature observations
- 1Water Resources Section, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, 2600 GA Delft, The Netherlands
- 2Fluid Mechanics Section, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, 2600 GA Delft, The Netherlands
- 3Department of Biological and Ecological Engineering, Oregon State University,116 Gilmore Hall, Corvallis, OR 97331, USA
- 4Department Environment and Agro-biotechnologies, Centre de Recherche Public – Gabriel Lippmann, 41, rue du Brill, 4422 Belvaux, Luxembourg
- 5Department of Water Engineering, UNESCO-IHE, Westvest 7, 2611 AX Delft, The Netherlands
Abstract. Distributed temperature data are used as input and as calibration data for an energy based temperature model of a first order stream in Luxembourg. A DTS (Distributed Temperature Sensing) system with a fiber optic cable of 1500 m was used to measure stream water temperature with 1 m resolution each 2 min. Four groundwater inflows were identified and quantified (both temperature and relative discharge). The temperature model calculates the total energy balance including solar radiation (with shading effects), longwave radiation, latent heat, sensible heat and river bed conduction. The simulated temperature is compared with the observed temperature at all points along the stream. Knowledge of the lateral inflow appears to be crucial to simulate the temperature distribution and conversely, that stream temperature can be used successfully to identify sources of lateral inflow. The DTS fiber optic is an excellent tool to provide this knowledge.