Temperature profile data collected using BT and XBT casts in the TOGA Area - Pacific Ocean from NOAA Ship RESEARCHER from 1985-09-17 to 1985-10-16 (NODC Accession 8700251)

Temperature profile data were collected using XBT and BT casts from NOAA Ship RESEARCHER in the TOGA Area - Pacific Ocean from 17 September 1985 to 16 October 1985. Data were collected by the US Coast Guard. 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.

1985年9月17日至10月16日，科研人员于太平洋热带海洋全球大气（TOGA）研究区域，通过美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）“研究者号”科考船搭载的投弃式温深仪（XBT）与温深仪（BT）获取了温度剖面数据。本次数据采集工作由美国海岸警卫队完成，后续由国家海洋学数据中心（National Oceanographic Data Center, NODC）将数据处理为符合其标准的通用温深仪输出（Universal Bathythermograph Output, UBT）格式。完整的格式说明可通过NODC官网www.nodc.noaa.gov/General/NODC-Archive/bt.html查阅。
UBT文件格式专为存储投弃式温深仪（XBT）获取的温度-深度剖面数据而设计。标准型XBT可获取深度达450米或760米的温度剖面，若配备专用仪器，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、观测日期与时间。数据记录由温度-深度值对组成。与机械式温深仪（MBT）数据文件采用均匀5米间隔记录温度值不同，XBT数据文件中的温度值对应非均匀深度点——这些点为以可接受精度完整记录温度曲线所需的最少拐点数量。但在数据输出环节，用户可选择获取拐点处的原始温度值，或插值至均匀深度步长后的温度值。