Pressure from height (75-term equation)

Usage

gsw_p_from_z(z, latitude, geo_strf_dyn_height, sea_surface_geopotential)

Arguments

z: height, zero at surface (but note last 2 args) and positive upwards [ m ]
latitude: latitude in decimal degrees, positive to the north of the equator. (This is called lat in the TEOS-10 Matlab code.)
geo_strf_dyn_height: vector of same length as z and latitude, indicating dynamic height [ m^2/s^2 ]. If not supplied, this defaults to a vector of 0 values, with length matching that of z.
sea_surface_geopotential: vector of same length as z and latitude, indicating geopotential at zero sea pressure [ m^2/s^2 ]. If not supplied, this defaults to a vector of 0 values, with length matching that of z.

Value

sea pressure [ dbar ]

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.

Historical Note

The geo_strf_dyn_height and sea_surface_geopotential parameters were added in GSW-R version 1.0-6.

References

http://www.teos-10.org/pubs/gsw/html/gsw_p_from_z.html

Examples

z <- -c(10, 50, 125, 250, 600, 1000)
latitude <- 4
p <- gsw_p_from_z(z, latitude)
stopifnot(all.equal(p/1e3, c(0.010055726724518, 0.050283543374874, 0.125731858435610,
                             0.251540299593468, 0.604210012340727, 1.007990337692001)))