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Oxygen Solubility in Seawater (GSW variables)

Source: R/gsw.R
gsw_O2sol.Rd

Computes oxygen concentration for seawater that is equilibrium with vapour-saturated air at standard atmospheric pressure (101.325 kPa, i.e. for sea pressure of 0dbar). The formula, not created by the SCOR/IAPSO Working Group 127 nor approved by the IOC, is stated in the TEOS-10 documentation to be from Benson and Krause (1984), as fitted by Garcia and Gordon (1992, 1993). That formulation is framed in UNESCO-era water properties, so longitude and latitude are needed here, to convert to these quantities from Absolute Salinity and Conservative Temperature; see also gsw_O2sol_SP_pt, which is formulated in UNESCO terms.

Usage

gsw_O2sol(SA, CT, p, longitude, latitude)

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

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

Oxygen solubility in micro-moles per kg.

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_O2sol.html

See also

Other things related to oxygen: gsw_O2sol_SP_pt()

Examples

SA <- c(34.7118, 34.8915, 35.0256, 34.8472, 34.7366, 34.7324)
CT <- c(28.8099, 28.4392, 22.7862, 10.2262,  6.8272,  4.3236)
p <- c(      10,      50,     125,     250,     600,    1000)
latitude <- c(4,       4,       4,       4,       4,       4)
longitude <- c(188,  188,     188,     188,     188,     188)
O2sol <- gsw_O2sol(SA,CT,p,longitude,latitude)
stopifnot(all.equal(O2sol/100, c(1.949651126384804, 1.958728907684003,
            2.148922307892045, 2.738656506758550, 2.955109771828408,
            3.133584919106894)))