Ocean salinity was recorded at 10 second intervals by a Seabird Electronics SBE 37 microCAT CTD at a nominal depth of 100 m in McMurdo Sound at 77.6152 °S, 164.8821 °E. The dates covered by the salinity observations at 100 m depth are from 28-10-2016 06:43:11 UTC to 13-11-2016 21:59:51 UTC. The salinity is reported in units of practical salinity. Ocean temperature was recorded at 10 second intervals by a Seabird Electronics SBE 56 thermistor at a nominal depth of 75 m in McMurdo Sound at 77.6152 °S, 164.8821 °E. The dates covered by the temperature observations at 75 m depth are from 3-11-2017 08:26:01 UTC to 20-11-2017 23:00:01 UTC. The temperature is reported in units of °C in the ITS-90 temperature scale.