Physical oceanographic data during Antarctic research cruise by Hakuho-Maru in 2016 (KH-16)

The main target of physical oceanography section during this R/V Hakuho-Maru cruise is to describe the water properties of the Cape Darnley Bottom Water (CDBW) - its origin, distribution, and long-term change. The target area is the region spanning from a deep part in the Weddell-Enderby Basin to shallower continental shelf region off Cape Darnley, East Antarctica. Conductivity Temperature Depth (CTD)/ Rosette Multi-Sampler (RMS) observations were conducted for 17 stations in February 2016. Seabird SBE911plus CTD system/SBE32 RMS was used.

Water samples for salinity were collected to calibrate the CTD sensors. Bottle salinity analysis was done by Autosal8400B (Guildline) at Laboratory No.5. Measurements were done for 122 standard/samples on 17-18 February after all CTD casts completed. Room temperature were controlled within 22.5-23.1 degC range. Bottle salinity shows a generally good determination. Some outlier values are found for near-surface waters. It seems to have a slight pressure dependency. Compared to the large signal, no clear temporal/inter-station drift was found. Hence the pressure-dependent offset was corrected for CTD output.