Seabird CTD processing software consists of many programs running under the Windows 95 operating system. The initial CTD processing program (SEASAVE) is used either in real-time or with existing raw data sets to:
Once the CTD data are reduced to a standard-format time-series, they can be manipulated in a number of ways. Channels can be additionally filtered. The time-series can be split up into shorter time-series or pasted together to form longer time-series. A time-series can be transformed into a pressure-series, or a different interval time-series. Calibration corrections to the series are maintained in separate files and are applied whenever the data are accessed.
Seabird data acquisition software acquired and processed the CTD data in real-time, providing calibrated, processed data for interactive plotting and reporting during a cast. The 25 hz data from the CTD were filtered, response corrected and averaged to a 2 hz time-series. Sensor correction and calibration models were applied to pressure, temperature, conductivity and O2. Rosette trip data were extracted from this time-series in response to trip initiation and confirmation signals. The calibrated 2 hz time-series data were stored on disk (as was the 25 hz raw data) and were available in real-time for reporting and graphical display. At the end of the cast, various consistency and calibration checks were performed, and a 1.0 db pressure series of the entire cast was generated and subsequently used for reports and plots.
CTD plots generated at the completion of the deployment were checked for potential problems. The pairs of PRT temperature sensors, conductivity sensors and oxygen sensors were inter-calibrated and checked for sensor drift. The CTD conductivity sensors were monitored by comparing CTD values to check sample conductivities and by deep TS comparisons with adjacent stations. The CTD dissolved O2 sensors were calibrated with check sample data.