gsw_deltaSA_from_SP: Absolute Salinity Anomaly from Practical Salinity

View source: R/gsw.R

gsw_deltaSA_from_SPR Documentation

Absolute Salinity Anomaly from Practical Salinity


Absolute Salinity Anomaly from Practical Salinity


gsw_deltaSA_from_SP(SP, p, longitude, latitude)



Practical Salinity (PSS-78) [ unitless ]


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


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


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


deltaSA Absolute Salinity Anomaly [ g/kg ]

Implementation Note

This R function uses a wrapper to a C function contained within the GSW-C system as updated 2021-12-28 at 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 website. Therefore, in the interests of making GSW-R be self-contained, a copy was downloaded from on 2022-05-25, the .mat file was stored in the developer/create_data directory of, and then the dataset used in GSW-R was created based on that .mat file.

Please consult to learn more about the various TEOS-10 software systems.


See Also

Other things related to salinity: gsw_C_from_SP(), gsw_SA_from_SP_Baltic(), gsw_SA_from_SP(), gsw_SA_from_Sstar(), gsw_SP_from_C(), gsw_SP_from_SA(), gsw_SP_from_SK(), gsw_SP_from_SR(), gsw_SP_from_Sstar(), gsw_SR_from_SP(), gsw_Sstar_from_SA(), gsw_Sstar_from_SP()


SP =   c(34.7118, 34.8915, 35.0256, 34.8472, 34.7366, 34.7324)
p =    c(     10,      50,     125,     250,     600,    1000)
lat =  c(      4,       4,       4,       4,       4,       4)
long = c(    188,     188,     188,     188,     188,     188)
deltaSA = gsw_deltaSA_from_SP(SP,p,long,lat)
stopifnot(all.equal(deltaSA, c(0.000167203365230, 0.000268836122231, 0.000665803155705,
                               0.002706154619403, 0.005652977406832,  0.009444734661606)))

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