DATA ACQUISITION AND FILTERING

The SARAGO data are visualized in real time on a PC workstation. Among these data, the trajectories on the water column and the probe measurements. This control workstation is also used for fine guidance of the tow-fish, by delivering or recovering cable layout. The data are then recorded and put on a separate workstation for filtering and processing.

The processing steps are as follows:

• georeferencing by GPS
• spikes removal and filtering
• data reduction by redundant variable elimination
• background noise elimination and smoothing
• calibration against CTD probe
• further calibration of SARAGO CTD (SBE9) probe against the ship's SBE11 at 1m depth intervals