To compute Mixed Layer Depth based on Subjective method

This function will help to determine mixed layer depth

% USAGE: MLD=ra_mld(salt,temp,Z,dT)
%
% PREREQUISITE: you must have installed SW Package or you must have
% following function from Sea Water package
% sw_den.m ; sw_dens.m; sw_dens0.m; sw_seck.m; sw_smow.m
%
% DESCRIPTION: This function determines Mixed Layer Depth (MLD) from profile data
% sets based on subjective method. If you have 3D data sets i.e. level, lat and lon and want
% to compute the MLD, then this function will be very handy. Because this function is
% specifically designed for those cases. However, it can evaluate MLD from profile data too.
%
% INPUTS:
% salt = Salinity profiles over the study region [psu], either 3D or vector
% temp = Temperature profiles over the study region [deg. C], either 3D or vector
% Z = Levels [m], Must be vector
% dT = temperature difference criterion [deg. C], Must be scalar
%
% OUTPUT:
% mld = mixed layer depth, spatial output [m]
%
% DISCLAIMER:
% Albeit this function is designed only for academic purpose, it can be implemented in
% research. Nonetheless, author does not guarantee the accuracy.