Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC MIDGETT in the Coastal Waters of California in support of the Integrated Global Ocean Services System (IGOSS) project from 07 February 1978 to 26 February 1978 (NODC Accession 7800213)

XBT data were collected from the USCGC MIDGETT in support of the Integrated Global Ocean Services System (IGOSS) project. Data were collected by the US Coast Guard (USCG) from 07 February 1978 to 26 February 1978. Data were processed by NODC to the NODC standard Universal Bathythermograph Output (UBT) format. Full format description is available from NODC at www.nodc.noaa.gov/General/NODC-Archive/bt.html. The UBT file format is used for temperature-depth profile data obtained using expendable bathythermograph (XBT) instruments. Standard XBTs can obtain profiles at depths of about 450 or 760 m. With special instruments, measurements can be obtained to 1830 m. Cruise information, position, date, and time are reported for each observation. The data record comprises pairs of temperature-depth values. Unlike the MBT data file, in which temperature values are recorded at uniform 5m intervals, the XBT Data File contains temperature values at non-uniform depths. These depths are at a minimum number of points ("inflection points") required to record the temperature curve to an acceptable degree of accuracy. On output, however, the user may request temperature values either at inflection points or interpolated to uniform depth increments.投弃式温深仪（expendable bathythermograph，XBT）数据采集自美国海岸警卫队米吉特号（USCGC MIDGETT），用于支撑全球海洋综合服务系统（Integrated Global Ocean Services System，IGOSS）项目。该批数据由美国海岸警卫队（US Coast Guard，USCG）于1978年2月7日至1978年2月26日期间采集完成。国家海洋数据中心（National Oceanographic Data Center，NODC）将这批数据处理为符合NODC标准的通用温深仪输出（Universal Bathythermograph Output，UBT）格式。完整的格式说明可从NODC官网的以下链接获取：www.nodc.noaa.gov/General/NODC-Archive/bt.html。 UBT文件格式用于存储通过投弃式温深仪（XBT）采集的温度-深度剖面数据。标准型XBT可获取深度约450米或760米的温度剖面；若使用特制仪器，最大测量深度可达1830米。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。与机械式温深仪（Mechanical Bathythermograph，MBT）数据文件不同，后者的温度值以固定5米的间隔记录，而XBT数据文件中的温度值对应非均匀分布的深度。这些深度点为将温度曲线记录至可接受精度所需的最少测点，即“拐点”。但在数据输出环节，用户可选择获取拐点处的原始温度值，或是将数据插值至均匀深度间隔后再获取温度值。