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Geostrophic Dynamic Height Anomaly (Piecewise-Constant Profile)

Usage

gsw_geo_strf_dyn_height_pc(SA, CT, delta_p)

Arguments

SA

Absolute Salinity [ g/kg ]. The valid range for most `gsw` functions is 0 to 42 g/kg.

CT

Conservative Temperature [ degC ].

delta_p

difference in sea pressure between the deep and shallow limits of layers within which SA and CT are assumed to be constant. Note that delta_p must be positive.

Value

A list containing dyn_height, the dynamic height anomaly [ m^2/s^2 ], and p_mid [ dbar ], the pressures at the layer centres. Note that the dynamic height anomaly unit, also known as a "dynamic meter", corresponds to approximately 1.02 metres of sealevel height (see e.g. Talley et al., 2011. Descriptive Physical Oceanography, Edition 6. Elsevier).

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

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)
delta_p <- c(10,      40,      75,     125,     350,     400)
r <- gsw_geo_strf_dyn_height_pc(SA, CT, delta_p)
stopifnot(all.equal(r$dyn_height, c(-0.300346215853487, -1.755165998114308, -4.423531083131365,
                                    -6.816659136254657, -9.453175257818430, -12.721009624991439)))
stopifnot(all.equal(r$p_mid/1e2, c(0.050000000000000, 0.300000000000000, 0.875000000000000,
                                   1.875000000000000, 4.250000000000000, 8.000000000000000)))