Practical Salinity Scale PSS

This standard seawater has since proven problematic because it is based on real seawater, whose conductivity is influenced by concentration variations in the nonconservative ions and subtle fluctuations in the ratios of the major ions. To eliminate these issues, a practical salinity scale (PSS-78) was adopted by international agreement in 1978. As a... 

For the simplicity of calculations, we have discussed salinity in units of g/kg. This Absolute Salinity differs from the commonly measured Practical Salinity (scale PSS-78) by about 0.5% (Millero andLeung, 1976 Feistel, 2003 Jackett etal., 2006 Millero et al., 2008). For the estimates in this section, this difference is quantitatively irrelevant. The density anomaly of the Baltic Sea is even less than this, up to about 0.01 %, and is ignored here as well (Millero and Kremling, 1976). 

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