title: Using Diurnal Temperature Signals to Infer Vertical Groundwater-Surface Water Exchange.
abstract: Heat is a powerful tracer to quantify fluid exchange between surface water and groundwater. Temperature time series can be used to estimate pore water fluid flux, and techniques can be employed to extend these estimates to produce detailed plan-view flux maps. Key advantages of heat tracing include cost-effective sensors and ease of data collection and interpretation, without the need for expensive and time-consuming laboratory analyses or induced tracers. While the collection of temperature data in saturated sediments is relatively straightforward, several factors influence the reliability of flux estimates that are based on time series analysis (diurnal signals) of recorded temperatures. Sensor resolution and deployment are particularly important in obtaining robust flux estimates in upwelling conditions. Also, processing temperature time series data involves a sequence of complex steps, including filtering temperature signals, selection of appropriate thermal parameters, and selection of the optimal analytical solution for modeling. This review provides a synthesis of heat tracing using diurnal temperature oscillations, including details on optimal sensor selection and deployment, data processing, model parameterization, and an overview of computing tools available. Recent advances in diurnal temperature methods also provide the opportunity to determine local saturated thermal diffusivity, which can improve the accuracy of fluid flux modeling and sensor spacing, which is related to streambed scour and deposition. These parameters can also be used to determine the reliability of flux estimates from the use of heat as a tracer.
authors.affiliation: School of Earth, Atmosphere and Environment, Monash University, Clayton, Victoria 3800, Australia.|The National Centre for Groundwater Research and Training, Flinders University, 326 Sturt Rd, Adelaide, South Australia 5001, Australia.
authors.forename: Dylan J
authors.initials: DJ
authors.lastname: Irvine
authors.affiliation: U. S. Geological Survey, Office of Groundwater, Branch of Geophysics, 11 Sherman Place Unit 5015, Storrs, CT 06269.
authors.forename: Martin A
authors.initials: MA
authors.lastname: Briggs
authors.affiliation: Department of Earth Sciences, Syracuse University 204 Heroy Geology Laboratory, Syracuse, NY 13244.
authors.forename: Laura K
authors.initials: LK
authors.lastname: Lautz
authors.affiliation: Maine Geological Survey, 93 State House Station, Augusta, ME 04333.
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Gordon
authors.affiliation: Earth and Planetary Sciences, McGill University, 3450 University Street, Montreal, Quebec, Canada H3A 0E8.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: McKenzie
authors.affiliation: School of Earth, Atmosphere and Environment, Monash University, Clayton, Victoria 3800, Australia.|The National Centre for Groundwater Research and Training, Flinders University, 326 Sturt Rd, Adelaide, South Australia 5001, Australia.
authors.forename: Ian
authors.initials: I
authors.lastname: Cartwright
mesh_terms: D060587:Groundwater; D006358:Hot Temperature; D015203:Reproducibility of Results; D013696:Temperature; D014867:Water
chemical_list: D014867:Water