Quantification of the contribution of the Beauce groundwater aquifer to the discharge of the Loire River using thermal infrared satellite imaging

Abstract

Abstract. Seven Landsat thermal infrared (TIR) images taken over the period 2000-2010 were used to establish longitudinal temperature profiles of the middle Loire River where it flows above the Beauce aquifer. The groundwater discharge along the river course was quantified for each identified groundwater catchment area using a heat budget based on temperature variations of the Loire River estimated from the TIR images. The results showed that 75 % of the temperature differences, between in situ observations and TIR image-based estimations, remained within the ±1 • C interval. The main discharge area of the Beauce aquifer into the Loire River was located between river kilometers 630 and 650, where there was a temperature drop of 1-1.5 • C in the summer and a rise of 0.5 • C in winter. According to the heat budgets, groundwater discharge was higher during the winter period (13.5 m 3 s −1 ) than during the summer period (5.3 m 3 s −1 ). These findings are in line with the results of both a groundwater budget and a process-based distributed hydrogeological model. Groundwater input was also found to be higher during the Loire's flow recession periods.

A practitioner's guide to thermal infrared remote sensing of rivers and streams: recent advances, precautions and considerations

“…Here, the magnitude of temperature heterogeneity caused by heat inputs from tributaries and power plants was observed to vary substantially between summer and winter months. In a similar investigation, Landsat 7 imagery of the Loire River, France, was used to understand links between temporal variability in longitudinal temperature patterns and groundwater exfiltration . By combining TIR data with heat budget modeling, the authors showed that seasonal variations in water temperature heterogeneity are indicative of groundwater discharge variability.…”

Influence of landscape and hydrological factors on stream–air temperature relationships at regional scale

“…The Tw variability, described by metrics of flow magnitude, frequency, duration, timing, and rate of change, on various timescales (Jones & Schmidt, 2018), is influenced by complex processes related to atmospheric, hydrogeological, geomorphic, and landscape characteristics and anthropogenic pressures, which could interact at multiple spatial scales (Caissie, 2006;Hannah & Garner, 2015). Numerous studies have highlighted the importance of riparian forest and groundwater inflows in moderating Tw variability (Dugdale, Malcolm, Kantola, & Hannah, 2018;Garner, Malcolm, Sadler, & Hannah, 2017;Kelleher et al, 2012;Lalot et al, 2015;Loicq, Moatar, Jullian, Dugdale, & Hannah, 2018). Identifying the main controlling factors of Tw variability remains an important task to target streams sensitive to climate change and to develop mitigation action to preserve aquatic ecosystems (Jackson et al, 2018).…”

LakeSST: Lake Skin Surface Temperature in French inland water bodies for 1999–2016 from Landsat archives

“…Schneider and Hook, 2010;Politi et al, 2012;Torbick et al, 2016). Because of its advantages, this technology has been increasingly applied to freshwater ecology in recent years (Dörnhöfer and Oppelt, 2016): satellite images have been used to study the water temperature of fluvial reaches (Lalot et al, 2015), reservoirs (Lamaro et al, 2013;Martí-Cardona et al, 2016), lakes (Marti-Cardona et al, 2008;Crosman and Horel, 2009) and crater lakes (Trunk and Bernard, 2008), as well as to monitor the thermal plumes from power plants (Zoran, 2011).…”