Temperature profile data collected using XBTs from the HAKUSAN MARU from the Pacific Ocean during the Thermal Structure Monitoring Program in the Pacific (TRANSPAC) project, 06 May 1977 to 13 May 1977 (NODC Accession 8100425)

Temperature profile data were collected using bathythermograph (BT/XBT) casts from HAKUSAN MARU in the Pacific Ocean from May 6, 1977 to May 13, 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5月6日至13日，科研船“白山丸（HAKUSAN MARU）”于太平洋海域通过深水温度剖面仪（bathythermograph, BT/XBT）投测作业，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）提交，作为太平洋热结构监测计划（TRANSPAC）项目的组成部分。美国国家海洋数据中心（National Oceanographic Data Center, NODC）已将数据处理为符合其标准的通用深水温度剖面仪输出（Universal Bathythermograph Output, UBT）格式。有关BT的完整说明可访问网址：http://www.nodc.noaa.gov/General/NODC-Archive/bt.html。

UBT格式存储了通过投弃式深水温度剖面仪（expendable bathythermograph, XBT）采集得到的温深剖面数据。每条观测记录均附带航次信息、观测位置、观测日期与时间，数据记录由多组温深数值对构成。与每5米等间隔记录温度值的MBT数据文件不同，XBT数据文件的温度值对应非均匀分布的深度，这些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的最大探测深度可达450米或760米；若使用特制仪器，探测深度可达1830米。