Using temperature to trace flow patterns is an inexpensive, yet effective method in hydrology research. Since groundwater carries heat, temperature works as a method of tracing groundwater-stream water interactions and subsurface flow paths (Anderson 2005). Comparing temperature fluctuations and patterns across varying locations and depths below surface can indicate the flow paths moisture takes during and/or after precipitation events. Temperature also has an effect on hydraulic conductivity and infiltration; two hydrologic properties that can be studied using heat tracers. In research involving the interaction between ground and stream water, temperature is indicative of gaining and loosing reaches. M. P. Anderson has written a detailed article on the importance and effectiveness of using temperature as a groundwater tracer.
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