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Ratios of changes in SA, CT and p that occur when frazil ice forms due to changes in pressure upon the mixture of seawater and ice.

Usage

gsw_frazil_ratios_adiabatic_poly(SA, p, w_Ih)

Arguments

SA

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

p

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

w_Ih

initial mass fraction (ice) / (water + ice)

Value

a list containing dSA_dCT_frazil, dSA_dP_frazil and dCT_dP_frazil.

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)
p <- c(        10,        50,       125,       250,       600,      1000)
w_Ih <- c(    0.9,      0.84,       0.4,      0.25,      0.05,      0.01)
r <- gsw_frazil_ratios_adiabatic_poly(SA, p, w_Ih)
stopifnot(all.equal(r$dSA_dCT_frazil,
    c(3.035308957896530, 1.932631198810934, 0.613220785586734,
     0.516106221687200, 0.436657158542033, 0.425827675768018)))
stopifnot(all.equal(r$dSA_dP_frazil/1e-6,
    c(-0.197512213108610, -0.133280971893621, -0.045599951957139,
      -0.038820466574251, -0.033548047632788, -0.033352365425407)))
stopifnot(all.equal(r$dCT_dP_frazil/1e-7,
    c(-0.650715350062703, -0.689634794137768, -0.743613932027895,
     -0.752179782823459, -0.768292629045686, -0.783236208526200)))