Compute seawater thermal conductivity, in $$W m^{-1\circ}C^{-1}$$

swThermalConductivity(salinity, temperature = NULL, pressure = NULL)

## Arguments

salinity salinity (PSU), or a ctd object, in which case temperature and pressure will be ignored. in-situ temperature ($$^\circ$$C), defined on the ITS-90 scale; see “Temperature units” in the documentation for swRho(). pressure (dbar)

## Value

Conductivity of seawater in $$W m^{-1\,\circ}C^{-1}$$. To calculate thermal diffusivity in $$m^2/s$$, divide by the product of density and specific heat, as in the example.

## Details

Caldwell's (1974) detailed formulation is used. To be specific, his equation 6 to calculate K, and his two sentences above that equation are used to infer this to be K(0,T,S) in his notation of equation 7. Then, application of his equations 7 and 8 is straightforward. He states an accuracy for this method of 0.3 percent. (See the check against his Table 1 in the “Examples”.)

## References

Caldwell, Douglas R., 1974. Thermal conductivity of seawater, Deep-sea Research, 21, 131-137.