Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC MIDGETT in the North Pacific Ocean in support of the Integrated Global Ocean Services System (IGOSS) project from 07 November 1973 to 01 May 1974 (NODC Accession 7400463)

XBT data were collected from the USCGC MIDGETT in support of the Integrated Global Ocean Services System (IGOSS) project. Data were collected by the US Coast Guard (USCG) from 07 November 1973 to 01 May 1974. 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数据由美国海岸警卫队“米杰特”号（USCGC MIDGETT）收集，以支持综合全球海洋服务系统（IGOSS）项目。这些数据由美国海岸警卫队（USCG）于1973年11月7日至1974年5月1日期间采集，并经NODC处理为NODC标准的通用深度温度计输出（UBT）格式。完整的格式说明可从NODC官网获取：www.nodc.noaa.gov/General/NODC-Archive/bt.html。

UBT文件格式用于存储通过消耗性深度温度计（XBT）获取的温深剖面数据。标准XBT可获取约450米或760米深度的剖面数据，使用特殊仪器则可测量至1830米。每条观测记录包含航行信息、位置、日期和时间，数据记录由温度-深度值对组成。与MBT数据文件中温度值以5米均匀间隔记录不同，XBT数据文件中的温度值位于非均匀深度处。这些深度点为记录温度曲线所需的最少“拐点”，以确保可接受的精度。不过，用户在输出时可选择获取拐点处的温度值，或插值得到均匀深度增量的温度值。