oce (version 0.9-14)

swConductivity: Seawater thermal conductivity

Description

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

Usage

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

Arguments

salinity

salinity [PSU], or a ctd object, in which case temperature and pressure will be ignored.

temperature

in-situ temperature [$^\circ$C]

pressure

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

If the first item is ctd object, then the salinity, temperature and pressure values will be extracted from it, and used in the calculation.

Note that this is provisional code only!

To do: Fill in a summary of Caldwell's technique.

To do: Compare this with Caldwell's stated uncertainty.

Caution. The results differ from Fofonoff's (1962) table 5 by 0.1 percent at 35PSU, and by under 1 percent for fresh water.

References

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

Fofonoff, N. P., 1962. Physical properties of sea-water, The Sea, 1, 3-30.

Examples

library(oce)
cond <- swConductivity(10,35,100); # 0.618569
diffusivity <- cond / (swRho(10,35,100) * swSpecificHeat(10,35,100))