Temperature profile data collected using XBTs from the HIEI MARU from the Pacific Ocean during the Thermal Structure Monitoring Program in the Pacific (TRANSPAC) project, 29 December 1976 to 06 January 1977 (NODC Accession 8100183)

Temperature profile data were collected using bathythermograph (BT/XBT) casts from HIEI MARU in the Pacific Ocean from December 29, 1976 to January 6, 1977. Data were submitted by Scripps Institution of Oceanography as part of the Thermal Structure Monitoring Program in the Pacific (TRANSPAC) project. Data were processed by NODC to the NODC standard Universal Bathythermograph Output (UBT) format. Full BT descriptions are available at http://www.nodc.noaa.gov/General/NODC-Archive/bt.html.

The UBT format contains temperature-depth profile data obtained using expendable bathythermograph (XBT) instruments. Cruise information, position, date and time were reported for each observation. The data record was comprised of pairs of temperature-depth values. Unlike the MBT Data File, in which temperature values were recorded at uniform 5 m intervals, the XBT data files contained temperature values at non-uniform depths. These depths were recorded at the minimum number of points (''inflection points'') required to accurately define the temperature curve. Standard XBTs can obtain profiles to depths of either 450 or 760 m. With special instruments, measurements can be obtained to 1830 m.

1976年12月29日至1977年1月6日期间，研究人员于太平洋海域开展科考作业，依托"日映丸（HIEI MARU）"号科考船搭载的海水温深仪（bathythermograph，BT/XBT）投放观测，采集得到温度剖面数据。该批数据由斯克里普斯海洋研究所（Scripps Institution of Oceanography）作为太平洋热结构监测计划（TRANSPAC）项目的组成部分提交。国家海洋数据中心（National Oceanographic Data Center，NODC）将原始数据处理为符合NODC标准的通用温深仪输出（Universal Bathythermograph Output，UBT）格式。完整的温深仪相关说明可访问以下网址：http://www.nodc.noaa.gov/General/NODC-Archive/bt.html。

UBT格式存储了使用抛弃式温深仪（expendable bathythermograph，XBT）采集得到的温度-深度剖面数据。每份观测记录均包含航次信息、观测位置、观测日期与时间，数据记录由多组温度-深度数值对构成。与采用均匀5米间隔记录温度值的机械温深仪（Mechanical Bathythermograph，MBT）数据文件不同，XBT数据文件中的温度值对应非均匀深度。此类深度仅记录了精准刻画温度曲线所需的最少测点，即"拐点（inflection points）"。标准XBT可获取深度达450米或760米的温度剖面；若使用专用仪器，测量深度可达1830米。