PhD 7 : Multi-scale thermal imaging of groundwater upwelling in stream valleys

Objectives:  Quantifying spatial and temporal variable groundwater upwelling in stream valleys by multi-scale thermal imaging

Expected Results: The ability of stream networks to drain landscapes depends on hydrologic connectivity across spatial scales from streams, riparian zones to the regional catchment. In combination with temporal changes (seasonal rainfall, temperature) this leads to spatial and temporal heterogeneity in groundwater upwelling in stream valleys through stream beds, riparian zones, and near hill slopes. The challenge is to develop a multi-scale thermal imagery method, where airborne and ground-based methods can quantify where, when, and how much groundwater escapes to stream valleys with special attention to how temperature-controlled changes in hydraulic parameters affect water storage/wetness/flooding/upwelling and direct seepage to streams. The ESR student will: (1) exploit current state-of-the art thermal imaging technologies and statistical methods/metrics for analysis of temperature signals to assess the use of temperature as a tracer for regional studies of groundwater upwelling and (2) integrate data in catchment-scale 3D heat-flow models to understand landscape and climate effects on spatio-temporal thermal and flow heterogeneity. HOBE observatory catchment will be used and the imaging and modelling techniques will be tested at TERENO river Selke and Emme sites. The innovative aspect is to investigate if thermal imaging is a feasible method for mapping upwelling at the scale of stream networks and linking these to temporal changes in hydraulic parameters, possible hot-spots of reactivity (ESR2) and water storage change observations from absolute quantum gravimeters (ESR8).

Supervisors: UCPH Copenhagen/ UNINE Neuchâtel, UFZ Leipzig
Contact : Peter Engesgaard pe(at)ign.ku.dk

More information on the Danish application site : link