Practical Conversion of Pressure to Depth

Abstract

A conversion formula between pressure and depth is obtained employing the recently adopted equation of state for seawater (Millero et al., 1980). Assuming the ocean of uniform salinity 35 NSU and temperature 0°C the following equation is proposed, namely, z = (1-c1)p − c2p2. If p is in decibars and z in meters c1 = (5.92 + 5.25 sin2ϕ) × 10−3, where ϕ is latitude and c2 = 2.21 × 10−6. To take account of the physical conditions in the water column a dynamic height correction is to be added but for many purposes this may be ignored.