oce (version 0.1-76)

sw.sigma: Seawater density anomaly

Description

Compute $\sigma$, the in-situ density of seawater, minus 1000 kg/m$^3$.

Usage

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

Arguments

S

either salinity [PSU] (in which case t and p must be provided) or a ctd object (in which case S, t and p are determined from the object, and must no

t

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

p

pressure [dbar]

Value

• In-situ density anomaly [kg/m$^3$].

Details

If the first argument is a ctd object, then salinity, temperature and pressure values are extracted from it, and used for the calculation.

Definition: $\rho(S,t,p)$ - 1000 kg/m$^3$.

See Also

Related density routines include: sw.rho to calculate in-situ density, sw.sigma.t to calculate an archaic quantity found in old textbooks, and sw.sigma.theta to calculate potential density anomaly relative to the surface pressure. If you are thinking of using sw.sigma, you probably want sw.sigma.theta.

Examples

sig <- sw.sigma(35, 13, 1000)	# 30.818}

<references>Fofonoff, P. and R. C. Millard Jr, 1983. Algorithms for
 computation of fundamental properties of seawater. <em>Unesco
 Technical Papers in Marine Science</em>, <b>44</b>, 53 pp

 Gill, A.E., 1982. <em>Atmosphere-ocean Dynamics</em>, Academic Press, New
 York, 662 pp.</references>

[object Object]

<keyword>misc</keyword>