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, 16 June 1977 to 23 June 1977 (NODC Accession 8100413)

Temperature profile data were collected using bathythermograph (BT/XBT) casts from HAKUSAN MARU in the Pacific Ocean from June 16, 1977 to June 23, 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.

本数据集的温度剖面数据采集于1977年6月16日至6月23日的太平洋海域，通过“白山丸”号（HAKUSAN MARU）搭载的温深仪（bathythermograph，BT/XBT）走航观测获取。该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）的一部分提交。美国国家海洋数据中心（National Oceanographic Data Center，NODC）已将数据处理为符合NODC标准的通用温深仪输出格式（Universal Bathythermograph Output，UBT）。完整的温深仪相关说明可查阅：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）获取的温度-深度剖面数据。每次观测均记录有航次信息、站位坐标、观测日期与时间。数据记录由温度-深度值对构成。与采用均匀5米间隔记录温度值的机械式温深仪（Mechanical Bathythermograph，MBT）数据文件不同，XBT数据文件的温度值对应非均匀深度。这些深度仅选取了精准刻画温度曲线所需的最少点数，即“拐点（inflection points）”。标准XBT可获取的剖面最大深度为450米或760米；若使用专用仪器，测量深度可达1830米。