gsw_sigma0: Potential density anomaly referenced to 0 dbar

In gsw: Gibbs Sea Water Functions

Potential density anomaly referenced to 0 dbar

Description

This uses the 75-term density equation, and returns potential density referenced to a pressure of 0 dbar, minus 1000 kg/m^3.

Usage

gsw_sigma0(SA, CT)

Arguments

SA	Absolute Salinity [ g/kg ]
CT	Conservative Temperature [ degC ]

Value

potential density anomaly [ kg/m^3 ]

Implementation Note

This R function uses a wrapper to a C function contained within the GSW-C system as updated 2021-12-28 at https://github.com/TEOS-10/GSW-C with git commit '98f0fd40dd9ceb0ba82c9d47ac750e935a7d0459'.

The C function uses data from the library/gsw_data_v3_0.mat file provided in the GSW-Matlab source code, version 3.06-11. Unfortunately, this version of the mat file is no longer displayed on the TEOS-10.org website. Therefore, in the interests of making GSW-R be self-contained, a copy was downloaded from http://www.teos-10.org/software/gsw_matlab_v3_06_11.zip on 2022-05-25, the .mat file was stored in the developer/create_data directory of https://github.com/TEOS-10/GSW-R, and then the dataset used in GSW-R was created based on that .mat file.

Please consult http://www.teos-10.org to learn more about the various TEOS-10 software systems.

References

http://www.teos-10.org/pubs/gsw/html/gsw_sigma0.html

See Also

Other things related to density: gsw_CT_from_rho(), gsw_CT_maxdensity(), gsw_SA_from_rho(), gsw_alpha_on_beta(), gsw_alpha_wrt_t_exact(), gsw_alpha_wrt_t_ice(), gsw_alpha(), gsw_beta_const_t_exact(), gsw_beta(), gsw_pot_rho_t_exact(), gsw_rho_alpha_beta(), gsw_rho_first_derivatives_wrt_enthalpy(), gsw_rho_first_derivatives(), gsw_rho_ice(), gsw_rho_t_exact(), gsw_rho(), gsw_sigma1(), gsw_sigma2(), gsw_sigma3(), gsw_sigma4(), gsw_specvol_alpha_beta(), gsw_specvol_anom_standard(), gsw_specvol_ice(), gsw_specvol_t_exact(), gsw_specvol()

Examples

SA <- c(34.7118, 34.8915, 35.0256, 34.8472, 34.7366, 34.7324)
CT <- c(28.8099, 28.4392, 22.7862, 10.2262,  6.8272,  4.3236)
sigma0 <- gsw_sigma0(SA,CT)
stopifnot(all.equal(sigma0, c(21.797900819337656, 22.052215404397316, 23.892985307893923,
                              26.667608665972011, 27.107380455119710, 27.409748977090885)))

gsw documentation built on Oct. 16, 2022, 5:06 p.m.