Temperature profile data collected using XBTs from the YAMASHIN MARU from the Pacific Ocean during the Thermal Structure Monitoring Program in the Pacific (TRANSPAC) project, 10 January 1977 to 18 January 1977 (NODC Accession 8100199)

Temperature profile data were collected using bathythermograph (BT/XBT) casts from YAMASHIN MARU in the Pacific Ocean from January 1, 1977 to January 18, 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.

1977年1月1日至1月18日，科研船“山下丸”（YAMASHIN MARU）于太平洋海域通过温深仪（bathythermograph，BT/XBT）测站采集了温度剖面数据。该数据集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）项目的一部分提交。美国国家海洋数据中心（National Oceanographic Data Center，NODC）将数据处理为符合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http://www.nodc.noaa.gov/General/NODC-Archive/bt.html。

UBT格式包含通过投弃式温深仪（expendable bathythermograph，XBT）仪器获取的温度-深度剖面数据。每次观测均记录了航次信息、位置、日期与时间。数据记录由温度-深度值对组成。与以均匀5米间隔记录温度值的MBT数据文件不同，XBT数据文件的温度值对应的深度并不均匀。这些深度仅记录了精准刻画温度曲线所需的最少点数，即“拐点（inflection points）”。标准XBT可获取深度达450米或760米的剖面数据；搭配专用仪器时，测量深度可达1830米。