The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The National Oceanic and Atmospheric Administration (NOAA)/Atmospheric Turbulence and Diffusion Division (ATDD) Soil Temperature Dataset is one of several sub-surface datasets provided for the Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP) Near Surface Observation Data Set (NESOB) 1997 project. This dataset contains data from one station, the Little Washita watershed long term flux site, within the NESOB 1997 domain (100.5W to 94.5W longitude and 34N to 39N latitude) and time period (01 April 1997 through 30 September 1997). Soil Temperature is sampled every 2 seconds with a datalogger and multiplexor (CR21x, Campbell Scientific, Inc.), and averages are computed every 30 minutes. A laptop computer retrieves the soil temperature data from the CR21X datalogger every 30 minutes and appends the data to an existing file. After midnight, the data are copied to separate files with a name, year, and calendar day header. The computer is equipped with a modem and cellular phone in order to retrieve the data and conduct occasional system checks. On average, data are retrieved from the laptop computers about once every two days. The NOAA/ATDD Soil Temperature Dataset contains eight metadata parameters and eighteen data parameters and flags. The metadata parameters describe the date, time, network, station and location at which the data were collected. Data values are valid for the 30 minutes preceding the time of observation, and all times are UTC. The data parameters consist of triplets for each depth.