This data release consists of two datasets, each accessible in its own child page, collected at the North Chevalier Field Disposal Area (Site 11) at Naval Air Station Pensacola in Florida. Site 11 is adjacent to Bayou Grande, which empties into Pensacola Bay. The first dataset consists of fiber-optic distributed temperature sensing data collected from March 13-March 16, 2018. The second dataset consists of specific conductance and temperature data collected from September 12, 2018-September 19,2022 from a series of shallow drivepoints installed along the shoreline at Site 11.

This child page contains fiber-optic distributed temperature sensing data collected from March 13-March 16, 2018 at the North Chevalier Field Disposal Area (Site 11) at Naval Air Station Pensacola in Pensacola Bay in Florida. A fiber-optic cable was run on the bottom of the bay parallel to the shoreline along an approximate 370-meter reach. The cable was installed near the shoreline just far enough offshore that most of it remained submerged at low tide. At the end of the reach, the cable was doubled back and installed parallel to, and approximately one meter offshore, of the first run. At the end of the second run, the cable was run ashore and connected to an Oryx Distributed Temperature Sensing (DTS) system. Near the DTS, several coils of the fiber optic cable were submerged in an ice slurry for the duration of the survey as a quality control measure. Temperature was measured every 15 minutes at one-meter intervals along the length of the cable. The temperature data, which are reported by the instrument as linear fiber distance, were georeferenced using a handheld Global Positioning System (GPS) for the purpose of relating known points in space to the distance along the fiber-optic cable. Additional details of the temperature survey can be found using the link to the companion U.S. Geological Survey (USGS) Scientific Investigations Report.

This child page contains specific conductance and temperature data collected from a series of temporary shallow drivepoints at Site 11 at Naval Air Station Pensacola, in Florida. The drivepoints were installed along the shoreline of Bayou Grande in six transects consisting of three to four drivepoints each. The drivepoints were hammered by hand into the sandy overburden until refusal in areas of potential groundwater discharge previously identified during a distributed temperature sensing survey. Installation depths below land surface ranged from a minimum of 2.7 feet to a maximum of 5.7 feet. Drivepoints were constructed from 1.25-inch polyvinyl chloride (PVC) well screens with 0.010-inch wide slots. The bottom of each drivepoint was sealed with a threaded PVC point and the top was finished with a PVC slip cap. Specific conductance and temperature sensors with internal data loggers were installed near the bottom of each drivepoint. A second shallower sensor was sometimes installed in a subset of the drivepoints near mid-depth. Data were collected at transects 1-3 from September 2018-September 2022 and from transects 4-6 from June 2019-September 2022. Data was collected at 15-minute intervals at all transects until May 6, 2021, when the interval was changed to 30 minutes. More detailed information regarding data collection can be found using the link to the companion U.S. Geological Survey Scientific Investigations Report.

This data release child item contains fiber-optic distributed temperature sensor (FO-DTS) data collected along the western unwalled shoreline of the Bremerton Naval Complex, Bremerton, Washington, USA from July 30, 2020, to August 11, 2020. Continuous profiles of water temperature were collected along a spatially georeferenced fiber optic cable deployed in an out-and-back U-shape with approximately 2- meter distance between the parallel cable lengths by a Sensornet® Oryx DTS FO-DTS (Fiber-optic distributed temperature sensor). Data were collected in a single ended configuration with two channels, Channel_1 and Channel_2, where water temperature was spatially averaged over 1.01- meter linear intervals by the Oryx instrument and collected at 15-minute intervals. Only the Channel_1 data were used for hydrologic interpretation and are contained in this release. Independent water-temperature data was collected at four locations by Hobo® Water Temp Pro v2 data-logging thermistors. Water-temperature data from thermistors were used as an independent water-temperature data calibration-check that was collected by data-logging thermistors verified by a National Institute of Standards and Technology (NIST)-certified thermistor with an accuracy of ±0.1 °C. A subset consisting of Channel_1 data from July 30, 2020 to August 7, 2020 was used for data visualization. This data was used to identify cold-water locations where groundwater, potentially containing elevated levels of metals and other toxic contaminants, may be discharging to Sinclair Inlet. The three zip folders contain: 1. "RAW_Data", which are the Oryx machine data text files (.ddf) from the fiber-optic temperature sensing tool measured with a time-series. These files include all data collected on Channel_1 by the fiber-optic distributed temperature sensor during its deployment along the longitudinal profile and internal instrument noise. 2. "Independant_Temperature_Data", which contains data collected independently by temperature data loggers during deployment. 3. "Visualization_Data", which contains geospatial data of points along the fiber-optic cable and USGS-DTSGUI (Domanski, et al., 2019) output files of FO-DTS temperature profiles by time and location.

In summer in Massachusetts, USA, preferential groundwater discharge zones are often colder than adjacent streambed areas that do not have substantial discharge. Therefore, discharge zones can efficiently be identified and mapped over space using heat as a tracer. This data release contains fiber-optic distributed temperature sensing (FO-DTS) data collected along the streambed interface of the main channel and tributaries of the upper Quashnet River, within approximately 1 km of Johns Pond, from June 14 to June 20, 2020. For these deployments a Salixa XT-DTS control unit (Salixa Ltd, Hertfordshire, UK) was used, and measurements were made over several day increments at 0.508 m linear resolution. Specific locations for collected data are located within the data files, and additional details are contained in the ‘readme’ files within each zipped data directory. Measured data in the form of Salixa instrument files are located in the 'Raw' data directory, including data collected along lengths of optical fiber that were not installed in the streams. The 'Processed' data directory contains data that have been aggregated from the original machine output files, spatially trimmed, and georeferenced. Additionally, simple summary streambed interface temperature statistics (mean, max, min, standard deviation) are listed by streambed location.

From June 25 to June 28, 2018, the U.S. Environmental Protection Agency (EPA) collected temperature measurements to help evaluate the thermal properties at two locations along the shoreline of City Lake in Fredericktown, MO. The in-situ temperature of surface water and saturated sediments was monitored to support calculations of seepage flux. Temperature measurements Celsius were collected every 30 minutes at depths of 0.04, 0.15,0.30,0.61, and 0.91 m below the water bottom. The thermal conductivity of saturated sediments was also measured.

From June 25 to June 28, 2018, the U.S. Environmental Protection Agency (EPA) collected temperature measurements to help evaluate the thermal properties at two locations along the shoreline of City Lake in Fredericktown, MO. The in-situ temperature of surface water and saturated sediments was monitored to support calculations of seepage flux. Temperature measurements Celsius were collected every 30 minutes at depths of 0.04, 0.15,0.30,0.61, and 0.91 m below the water bottom. The thermal conductivity of saturated sediments was also measured.

Fiber-optic distributed temperature sensing (FO-DTS) cables were deployed along the sediment/water interface to map high spatial resolution temperature variations along the streambed. These variations are used to detect zones of groundwater discharge. Data are to be used in conjunction with electromagnetic imaging (EMI) and ground penetrating radar (GPR) data. The combined dataset represents point in time mapping of preferential groundwater discharge points (FO-DTS), and the bed structure that controls where these points are located (GPR, EMI).

Fiber-optic distributed temperature sensing (FO-DTS) cables were deployed along the sediment/water interface to map high spatial resolution temperature variations along the streambed. These variations are used to detect zones of groundwater discharge. Data are to be used in conjunction with electromagnetic imaging (EMI) and ground penetrating radar (GPR) data. The combined dataset represents point in time mapping of preferential groundwater discharge points (FO-DTS), and the bed structure that controls where these points are located (GPR, EMI).

Natural heat is used as a tracer for a variety of physical hydrogeological process, including zones of preferential exchange between groundwater and surface water. Several types of instruments are used to measure the temperature of surface water and saturated sediments. This data release presents the results of fiber-optic distributed temperature sensing (FO-DTS) using temperature sensitive armored cables deployed along the riverbed interface. Data were collected over time (08/06/2015 to 09/24/2015) at 1.01 m spatial resolution along a reach of the Little Wind River, WY, USA. This study reach included an upstream shallow side channel where the cable was exposed to air over several short segments, and a downstream deeper section where the cable was generally installed within 5 m of the bank. The FO-DTS system was setup to collect a temperature measurement along this cable every 40 min; however, solar power to the control unit failed intermittently during the deployment period, especially later in the record, so the data are of inconsistent timestep. The processed data included in this release have been clipped to a cable length and time period of specific interest, as described in the local readme files.