swSigma0 {oce} | R Documentation |
Compute sigma, the potential density of
seawater (minus 1000 kg/m^3), referenced to various pressures,
i.e swSigma0
is referenced to the surface and is thus identical to
swSigmaTheta
, while swSigma1
is referenced to
1000dbar, swSigma2
is referenced to 2000dbar, swSigma2
is
referenced to 3000dbar, and swSigma4
is referenced to 4000dbar.
swSigma0(salinity, temperature, pressure, longitude=300, latitude=30, eos=getOption("oceEOS", default="gsw")) swSigma1(salinity, temperature, pressure, longitude=300, latitude=30, eos=getOption("oceEOS", default="gsw")) swSigma2(salinity, temperature, pressure, longitude=300, latitude=30, eos=getOption("oceEOS", default="gsw")) swSigma3(salinity, temperature, pressure, longitude=300, latitude=30, eos=getOption("oceEOS", default="gsw")) swSigma4(salinity, temperature, pressure, longitude=300, latitude=30, eos=getOption("oceEOS", default="gsw"))
salinity |
either practial salinity (in which case |
temperature |
in-situ temperature [degC], defined on
the ITS-90 scale; see “Temperature units” in the documentation for
|
pressure |
pressure [dbar] |
longitude |
longitude of observation (only used if |
latitude |
latitude of observation (only used if |
eos |
equation of state, either |
If the first argument is a ctd
object or section
object,
then salinity, etc., values are extracted from it, and used for the
calculation.
Definition: sigma_0=sigma_theta=rho(S,theta(S,t,p),0) - 1000 kg/m^3.
Potential density anomaly [kg/m^3].
Dan Kelley
See citations provided in the swRho
documentation.
Related density routines include: swSigmaTheta
, which
these functions employ, and also swRho
, and (mostly for
historical use) swSigmaT
.
swSigmaTheta(35, 13, 1000) swSigma0(35, 13, 1000) swSigma1(35, 13, 1000) swSigma2(35, 13, 1000) swSigma3(35, 13, 1000)