Temperature profile data collected using XBTs from the PACIFIC ARROW from the Pacific Ocean during the Thermal Structure Monitoring Program in the Pacific (TRANSPAC) project, 24 July 1977 to 01 August 1977 (NODC Accession 8100345)

Temperature profile data were collected using bathythermograph (BT/XBT) casts from PACIFIC ARROW in the Pacific Ocean from July 24, 1977 to August 1, 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自1977年7月24日至8月1日期间，太平洋海域“PACIFIC ARROW”航次利用深海测温仪（bathythermograph, BT/XBT）开展的观测作业。该数据由斯克里普斯海洋研究所提交，作为太平洋热结构监测计划（Thermal Structure Monitoring Program in the Pacific, TRANSPAC）项目的组成部分。数据已由美国国家海洋数据中心（National Oceanographic Data Center, NODC）处理为NODC标准通用深海测温仪输出（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海测温仪（expendable bathythermograph, XBT）获取的温度-深度剖面数据。每条观测记录均包含航次信息、观测位置、日期与时间，数据记录由温度-深度值对构成。与MBT数据文件不同——后者以均匀5米间隔记录温度值——XBT数据文件的温度值对应非均匀深度，这些深度以精准刻画温度曲线所需的最少点数（拐点）进行记录。标准投弃式深海测温仪可获取的剖面最大深度为450米或760米，使用特制仪器时，测量深度可达1830米。