Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC ACUSHNET in the Gulf of Mexico in support of the Integrated Global Ocean Services System (IGOSS) from 03 December 1976 to 08 December 1976 (NODC Accession 7601899)

XBT data were collected from the USCGC ACUSHNET in support of the Integrated Global Ocean Services System (IGOSS). Data were collected by the US Coast Guard from 03 December 1976 to 08 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.

本数据集的投弃式温深仪（Expendable Bathythermograph，简称XBT）数据采集自美国海岸警卫队ACUSHNET号舰艇，旨在支持全球海洋综合服务系统（Integrated Global Ocean Services System，简称IGOSS）的相关工作。该数据由美国海岸警卫队于1976年12月3日至12月8日期间采集。美国国家海洋数据中心（National Oceanographic Data Center，简称NODC）将数据处理为符合其标准的通用温深仪输出（Universal Bathythermograph Output，简称UBT）格式。完整的格式说明可从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温深仪采集的温度-深度剖面数据。标准型XBT可获取深度约450米或760米处的剖面数据；若使用特制仪器，测量深度可达1830米。每条观测记录均包含航次信息、观测位置、日期与时间，数据记录由温度-深度值对组成。与采用均匀5米间隔记录温度值的机械温深仪（Mechanical Bathythermograph，简称MBT）数据文件不同，XBT数据文件中的温度值对应非均匀深度。这些深度对应为以可接受的精度记录温度曲线所需的最少点数（即"inflection points"）。但在输出时，用户可选择获取拐点处的温度值，或将其插值为均匀深度间隔下的温度值。