Temperature, salinity, sigma-T, and pressure profile CTD data from R/V MELVILLE and GLACIER in the Southern Oceans (> 60 degrees South) from 19860304 to 19860331 (NODC Accession 9100082)

The observations were carried out from two vessels. One, the icebreaker Glacier, operated within the sea ice out to the vicinity of the ice edge. The second vessel, R/V Melville, operated in the open water seaward of the ice edge. Temperature and salinity (as conductivity) observations were made from both vessels using Neil Brown Mark IV CTD (conductivity/temperature/depth) profiling systems. Sixty-six CTD casts were made from the Glacier and 49 from the Melville. Most of the casts extended to depths greater than 500 m, and more than half extended to 1500 m.

CTD quality was of primary concern. The data were printed out and plotted during the field program, allowing a near real-time check on instrument performance and data quality. The data were also recorded digitally for later processing. The CTD used on the Glacier was calibrated prior to and following the cruise at the Northwest Regional Calibration Center in Bellevue, Washington. The CTDs on both vessels were calibrated regularly (typically every third or fourth cast) during the field program against temperature and salinity values obtained using rosette of Nansen sample bottles and deep sea reversing thermometers. The calibration data revealed a slight conductivity drift problem with the Glacier CTD system,and allowed development algorithm which was successfully used to correct the problem. The final data are accurate to within O.Ol deg C re and 0.01 ppt in salinity, Resolution was better than O.OO5 deg C and 0.005 ppt in these variables.

This text was taken from: Husby, D.M., and R.D. Muench, Hydrographic observations in the northwestern Weddell Sea marginal ice zone during March of 1986., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-96, 1988.

本观测由两艘科考船完成。其中破冰船“冰川号”（Glacier）在海冰覆盖区域内作业，最远抵达冰缘附近海域；另一艘为R/V梅尔维尔号（Melville），在冰缘外侧的开阔水域开展观测。两艘船均采用尼尔·布朗Mark IV型温盐深剖面系统（CTD，Conductivity/Temperature/Depth）开展温度与盐度（以电导率表征）观测。“冰川号”共完成66次CTD剖面投放，“梅尔维尔号”则完成49次。多数剖面的探测深度超过500米，其中半数以上可达1500米。

CTD数据质量为本次观测的核心关注点。野外作业期间，数据会被打印并绘制成图，以便对仪器性能与数据质量进行近实时检查；同时数据以数字形式存储，用于后续处理。“冰川号”搭载的CTD系统在航次前后均于华盛顿州贝尔维尤的西北区域校准中心完成校准。野外作业期间，两艘船的CTD系统均定期（通常每投放3至4次剖面后）采用南森采水器组与深海颠倒温度计获取的温盐值进行校准。校准数据显示“冰川号”的CTD系统存在轻微的电导率漂移问题，据此开发的校正算法成功解决了该问题。最终数据的温度精度优于±0.01℃，盐度精度优于±0.01 ppt，温度与盐度的分辨率分别优于0.005℃与0.005 ppt。

本文本源自：Husby D.M.与Muench R.D.于1988年发表的《1986年3月威德尔海西北边缘冰带的水文观测》，载于美国国家海洋和大气管理局（NOAA）技术备忘录NOAA-TM-NMFS-SWFC-96。