Temperature, salinity, sigma-T, and pressure profile CTD data from R/V MELVILLE and GLACIER in the Southern Oceans (> 60 degrees South) from 1986-03-04 to 1986-03-31 (NCEI 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 0.01 deg C re and 0.01 ppt in salinity, Resolution was better than 0.005 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.

Data has been processed by NODC to the NODC standard High-Resolution CTD/STD (F022) format.

The F022 format contains high-resolution data collected using CTD (conductivity-temperature-depth) and STD (salinity-temperature-depth) instruments. As they are lowered and raised in the oceans, these electronic devices provide nearly continuous profiles of temperature, salinity, and other parameters. Data values may be subject to averaging or filtering or obtained by interpolation and may be reported at depth intervals as fine as 1m. Cruise and instrument information, position, date, time and sampling interval are reported for each station. Environmental data at the time of the cast (meteorological and sea surface conditions) may also be reported. The data record comprises values of temperature, salinity or conductivity, density (computed sigma-t), and possibly dissolved oxygen or transmissivity at specified depth or pressure levels. Data may be reported at either equally or unequally spaced depth or pressure intervals. A text record is available for comments.