Sea pressure
Sea pressure is the difference between the pressure measured underwater by your RBR instrument and atmospheric pressure. The units of measurement are dbar (decibars).
\[\text{Sea pressure} = \text{absolute pressure} - \text{atmospheric pressure}\]
where pressure (in dbar) is the value measured directly by your RBR instrument.
Enter atmospheric pressure (in dbar) manually in the Parameters table under the Calibration tab in Ruskin. See Ruskin User Guide: Compact Instruments⁴. If not entered, Ruskin uses a default value of 10.1325dbar.