Practical Salinity from Preformed Salinity

gsw_SP_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

Practical Salinity (PSS-78) [ unitless ]

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.

Examples

Sstar <- c(34.7115, 34.8912, 35.0247, 34.8436, 34.7291, 34.7197)
p <- c(         10,      50,     125,     250,     600,    1000)
longitude <- 188
latitude <- 4
SP <- gsw_SP_from_Sstar(Sstar, p, longitude, latitude)
stopifnot(all.equal(SP, c(34.548646570969929, 34.727538423586189, 34.860549501859502,
                          34.681006826476434, 34.568065697992346, 34.560023926979518)))