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Calculate Absolute Salinity from Preformed Salinity, pressure, longitude, and latitude.

Usage

gsw_SA_from_Sstar(Sstar, p, longitude, latitude)

Arguments

Sstar

Preformed Salinity [ g/kg ]

p

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

longitude

longitude in decimal degrees, positive to the east of Greenwich. (This is called long in the TEOS-10 Matlab code.)

latitude

latitude in decimal degrees, positive to the north of the equator. (This is called lat in the TEOS-10 Matlab code.)

Value

Absolute Salinity [ g/kg ]

Details

If Sstar is a matrix and if its dimensions correspond to the lengths of longitude and latitude, then the latter are converted to analogous matrices with expand.grid.

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

Sstar <- c(34.7115, 34.8912, 35.0247, 34.8436, 34.7291, 34.7197)
p <- c(      10,      50,     125,     250,     600,    1000)
lat <- c(     4,       4,       4,       4,       4,       4)
long <- c(  188,     188,     188,     188,     188,     188)
SA <- gsw_SA_from_Sstar(Sstar, p, long, lat)
stopifnot(all.equal(SA, c(34.711724663585905, 34.891561223296009, 35.025594598699882,
                          34.847235885385913, 34.736694493054166, 34.732387111902753)))