Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC ACUSHNET in the North Pacific Ocean in support of the Integrated Global Ocean Services System (IGOSS) from 19 November 1978 to 22 November 1978 (NODC Accession 7800868)

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 19 November 1978 to 22 November 1978. 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.

本数据集的投弃式深度温度记录仪（XBT，expendable bathythermograph）数据采集自美国海岸警卫队ACUSHNET号，用于支持综合全球海洋服务系统（IGOSS，Integrated Global Ocean Services System）。数据由美国海岸警卫队于1978年11月19日至11月22日期间采集，后由国家海洋数据中心（NODC，National Oceanographic Data Center）按照其标准的通用深度温度记录仪输出格式（UBT，Universal Bathythermograph Output）进行处理。完整格式说明可通过NODC官网www.nodc.noaa.gov/General/NODC-Archive/bt.html获取。

UBT文件格式用于存储通过XBT仪器获取的温度-深度剖面数据。标准型XBT可获取约450米或760米深度的剖面数据；配备专用仪器时，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。数据记录由多组温度-深度值对构成。与温度值按均匀5米间隔记录的机械式深度温度记录仪（MBT）数据文件不同，XBT数据文件中的温度值对应非均匀深度，这些深度点为以可接受精度记录温度曲线所需的最少“拐点”数量。但在数据输出时，用户可选择按拐点输出温度值，或通过插值得到均匀深度增量下的温度值。