sound_absorption_sea_ainslie.m

function [alpha, Boric, MgSO4, H2O] = sound_absorption_sea_ainslie(T,S,D,f,pH)
% Inputs
%   T: temperature \ degree Celsius
%   S: salinity \ ppt
%   D: depth \ m
%   f: frequency \ kHz
%   pH: "potential of hydrogen"
% Outputs
%   alpha: absorption of sound in seawater \ dB/km

    D = D*1e-3;

    % Boric
    A1 = 0.106*exp((pH-8)./0.56);
    P1 = 1;
    f1 = 0.78*sqrt(S./35).*exp(T./26);
    Boric = (A1.*P1.*f1*(f.^2))./((f.^2)+(f1.^2));

    % MgSO4
    A2 = 0.52*(S./35).*(1+T./43);
    P2 = exp(-D./6);
    f2 = 42*exp(T./17);
    MgSO4 = (A2.*P2.*f2*(f.^2))./((f.^2)+(f2.^2));

    % H2O
    A3 = 0.00049*exp(-(T./27+D./17));
    P3 = 1;
    H2O = A3.*P3.*(f.^2);

    % Total
    alpha = Boric + MgSO4 + H2O;
end