sw.sigma {oce} | R Documentation |
Compute sigma, the in-situ density of seawater, minus 1000 kg/m^3.
sig <- sw.sigma(ctd) sig <- sw.sigma(S, t=NULL, p=NULL);
ctd |
an object of class "ctd ". |
S |
salinity [PSU] |
t |
in-situ temperature [degC] |
p |
pressure [dbar] |
In the first form, the argument is a ctd
object, from which the
salinity, temperature and pressure values are extracted and used to
for the calculation.
Definition: rho(S,t,p) - 1000 kg/m^3.
In-situ density anomaly [kg/m^3].
Dan Kelley
Fofonoff, P. and R. C. Millard Jr, 1983. Algorithms for computation of fundamental properties of seawater. Unesco Technical Papers in Marine Science, 44, 53 pp
Gill, A.E., 1982. Atmosphere-ocean Dynamics, Academic Press, New York, 662 pp.
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
.
sig <- sw.sigma(35, 13, 1000) # 30.818