HESS Hydrology and Earth System Sciences HESS Hydrol. Earth Syst. Sci. 1607-7938 Copernicus Publications Göttingen, Germany 10.5194/hess-15-1081-2011 Assessment of a vertical high-resolution distributed-temperature-sensing system in a shallow thermohaline environment Suárez F. 1 Aravena J. E. 2 Hausner M. B. 3 Childress A. E. 2 Tyler S. W. 1 Department of Geological Sciences and Engineering, University of Nevada, Reno, USA Department of Civil and Environmental Engineering, University of Nevada, Reno, USA Graduate Program of Hydrologic Sciences, University of Nevada, Reno, USA 30 03 2011 15 3 1081 1093 Copyright: © 2011 F. Suárez et al. 2011 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://hess.copernicus.org/articles/15/1081/2011/hess-15-1081-2011.html The full text article is available as a PDF file from https://hess.copernicus.org/articles/15/1081/2011/hess-15-1081-2011.pdf

In shallow thermohaline-driven lakes it is important to measure temperature on fine spatial and temporal scales to detect stratification or different hydrodynamic regimes. Raman spectra distributed temperature sensing (DTS) is an approach available to provide high spatial and temporal temperature resolution. A vertical high-resolution DTS system was constructed to overcome the problems of typical methods used in the past, i.e., without disturbing the water column, and with resistance to corrosive environments. This paper describes a method to quantitatively assess accuracy, precision and other limitations of DTS systems to fully utilize the capacity of this technology, with a focus on vertical high-resolution to measure temperatures in shallow thermohaline environments. It also presents a new method to manually calibrate temperatures along the optical fiber achieving significant improved resolution. The vertical high-resolution DTS system is used to monitor the thermal behavior of a salt-gradient solar pond, which is an engineered shallow thermohaline system that allows collection and storage of solar energy for a long period of time. The vertical high-resolution DTS system monitors the temperature profile each 1.1 cm vertically and in time averages as small as 10 s. Temperature resolution as low as 0.035 °C is obtained when the data are collected at 5-min intervals.

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