oce (version 0.1-75)

sw.conductivity: Seawater conductivity

Description

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

Usage

sw.conductivity(S, t=NULL, p=NULL)

Arguments

S

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

t

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

p

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 to for 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 <- sw.conductivity(10,35,100); # 0.618569
 diffusivity <- cond / (sw.rho(10,35,100) * sw.specific.heat(10,35,100))