Summary: | The dataset consists of 81 Underway CTD (UCTD) casts in the region north of Flemish Cap. The UCTD is an un-pumped profiling CTD, manufactured by the Oceanscience Group, that can be deployed from a moving ship. The UCTD measures temperature, conductivity, and pressure at 16 Hz. The pressure and its time derivative (descent rate) were low-pass filtered with a filter cutoff period of 2 s. The temperature and conductivity signals were also filtered, but with the filter cutoff period set to 0.25 s. Alignment of the temperature and conductivity was performed as a function of the instrument descent rate using an empirical relationship. Because of the rapid descent rate of the UCTD (up to 4 dbar/s), the measured temperature was corrected for the effect of viscous heating. The effect of the thermal mass of the conductivity cell was accounted for using the standard correction with the parameters determined as a function of the local instrument descent rate. The processed temperature, conductivity, and pressure were used to compute salinity, potential temperature, and potential density. Finally, the data were averaged into 1 dbar bins.
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