Temperature profiles from XBT casts from the DUANE from Ocean Weather Station C (OWS-C) in the North Atlantic Ocean from 13 March 1974 to 04 April 1974 (NODC Accession 7400359)

Bathythermograph data were collected from the DUANE within a 1-mile radius of Ocean Weather Station C (5245N 03530W) and in transit. Data were collected by the United States Coast Guard from 13 March 1974 to 04 April 1974. The platform was equipped and staffed to observe weather and sea conditions. Data were processed by NODC to the NODC standard Universal Bathythermograph Output (UBT) format. Full format description is available from NODC at www.nodc.noaa.gov/General/NODC-Archive/bt.html.

The UBT file format is used for temperature-depth profile data obtained using expendable bathythermograph (XBT) instrument. Standard XBTs can obtain profiles at depths of about 450 or 760 m. With special instruments, measurements can be obtained to 1830 m. Cruise information, position, date, and time are reported for each observation. The data record comprises pairs of temperature-depth values. Unlike the MBT data file, in which temperature values are recorded at uniform 5m intervals, the XBT Data File contains temperature values at non-uniform depths. These depths are at a minimum number of points ("inflection points") required to record the temperature curve to an acceptable degree of accuracy. On output, however, the user may request temperature values either at inflection points or interpolated to uniform depth increments.

本数据集的海水温度深度记录仪（Bathythermograph）数据采集自杜安号（DUANE）船，采集范围涵盖海洋气象站C（52°45′N 035°30′W）周边1英里海域及航行途中区域。数据由美国海岸警卫队于1974年3月13日至1974年4月4日期间采集。该观测平台配备专业观测设备并配备作业人员，用于开展气象与海洋状况监测。数据已由国家海洋数据中心（National Oceanographic Data Center, NODC）处理为NODC标准通用海水温度深度记录仪输出格式（Universal Bathythermograph Output, UBT）。完整格式说明可从NODC官网获取，网址为www.nodc.noaa.gov/General/NODC-Archive/bt.html。

UBT文件格式用于存储通过投弃式海水温度深度记录仪（expendable bathythermograph, XBT）获取的温度-深度剖面数据。标准型XBT可获取约450米或760米水深的温度剖面；若使用专用仪器，最大测量水深可达1830米。每份观测记录均包含航行信息、观测位置、观测日期与时间。数据记录由多组温度-深度数值对构成。与机械式海水温度深度记录仪（Mechanical Bathythermograph, MBT）数据文件不同，后者的温度值以固定5米间隔记录，而XBT数据文件中的温度值对应非均匀水深。这些水深点位仅为以可接受精度记录温度曲线所需的最少数量的“拐点”。在数据输出阶段，用户可选择获取拐点处的温度值，或通过插值得到均匀水深间隔下的温度值。