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Thermal expansion coefficient with respect to in-situ temperature.

Usage

gsw_alpha_wrt_t_exact(SA, t, p)

Arguments

SA

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

t

in-situ temperature (ITS-90) [ degC ]

p

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

Value

thermal expansion coefficient with respect to in-situ 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.

Examples

SA <- c(34.7118, 34.8915, 35.0256, 34.8472, 34.7366, 34.7324)
t <-  c(28.7856, 28.4329, 22.8103, 10.2600,  6.8863,  4.4036)
p <-  c(     10,      50,     125,     250,     600,    1000)
alpha_wrt_t_exact <- gsw_alpha_wrt_t_exact(SA,t,p)
stopifnot(all.equal(alpha_wrt_t_exact*1e3,
    c(0.325601747227247, 0.323448083851267, 0.281413883319329,
    0.172825692975230, 0.145569941503599, 0.128362986933288)))