Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC GALLATIN in the North Atlantic Ocean in support of the Integrated Global Ocean Services System (IGOSS) from 18 November 1976 to 20 December 1976 (NODC Accession 7601921)

XBT data were collected from the USCGC GALLATIN in support of the Integrated Global Ocean Services System (IGOSS). Data were collected by the US Coast Guard from 18 November 1976 to 20 December 1976. 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) instruments. 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.

XBT数据采集自美国海岸警卫队加拉丁号（USCGC GALLATIN），用于支撑全球海洋综合服务系统（Integrated Global Ocean Services System，IGOSS）。该数据由美国海岸警卫队于1976年11月18日至1976年12月20日期间采集。数据由国家海洋数据中心（National Oceanographic Data Center，NODC）按照其通用温深仪输出（Universal Bathythermograph Output，UBT）标准格式进行处理。完整的格式说明可从NODC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温深仪（Expendable Bathythermograph，XBT）采集的温度-深度剖面数据。标准XBT可获取最大深度约450米或760米的剖面数据。若使用专用仪器，测量深度可达1830米。每次观测均会记录航次信息、站位坐标、观测日期与时间。数据记录由多组温度-深度值对组成。与机械式温深仪（Mechanical Bathythermograph，MBT）数据文件不同，后者以固定5米间隔记录温度值，而XBT数据文件中的温度值对应非均匀深度。这些深度点为以可接受的精度记录温度曲线所需的最少拐点（inflection points）。但在数据输出时，用户可选择获取拐点处的温度值，或通过插值得到均匀深度间隔下的温度值。