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Thermal expansion coefficient with respect to Conservative Temperature

Source: R/gsw.R
gsw_alpha.Rd

Thermal expansion coefficient with respect to Conservative Temperature, using the 75-term equation for specific volume.

Usage

gsw_alpha(SA, CT, p)

Arguments

SA

Absolute Salinity [ g/kg ]. The valid range for most `gsw` functions is 0 to 42 g/kg.

CT

Conservative Temperature [ degC ].

p

sea pressure [dbar], i.e. absolute pressure [dbar] minus 10.1325 dbar

Value

thermal expansion coefficient with respect to Conservative Temperature [ 1/K ]

Implementation Note

This R function uses a wrapper to a C function contained within the GSW-C system as updated 2022-10-11 at https://github.com/TEOS-10/GSW-C with git commit `657216dd4f5ea079b5f0e021a4163e2d26893371`.

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_alpha.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_beta(), gsw_beta_const_t_exact(), gsw_infunnel(), gsw_pot_rho_t_exact(), gsw_rho(), gsw_rho_alpha_beta(), gsw_rho_first_derivatives(), gsw_rho_first_derivatives_wrt_enthalpy(), gsw_rho_ice(), gsw_rho_t_exact(), gsw_sigma0(), gsw_sigma1(), gsw_sigma2(), gsw_sigma3(), gsw_sigma4(), gsw_specvol(), gsw_specvol_alpha_beta(), gsw_specvol_anom_standard(), gsw_specvol_ice(), gsw_specvol_t_exact()

Examples

SA <- c(34.7118, 34.8915, 35.0256, 34.8472, 34.7366, 34.7324)
CT <- c(28.7856, 28.4329, 22.8103, 10.2600,  6.8863,  4.4036)
p <-  c(     10,      50,     125,     250,     600,    1000)
alpha <- gsw_alpha(SA,CT,p)
stopifnot(all.equal(alpha*1e3, c(0.324464211877393, 0.322610094680523, 0.281335030247435,
                                 0.173529986885424, 0.146898108553385, 0.130265123640082)))