This directory contains routines for generating ice drift  from 
a) A collection of DAILY files - uses icedrift.in file in Infiles
b) A CERSAT ice drift file - for use in data assimilation

icedrift2 : When called with no arguments it reads icedrift.in to get
            a initial position, number of DAILY files to read, and actual
            daily files.  It reads model ice drift from the DAILY files and
            calculates ice particle drift. 
            If you Compare the drift with IABP drift this can be used for validation
            purposes.

            When called with (5) arguments it takes as input the positions of 
            ice drift in a CERSAT ice drift file, and calculates corresponding
            ice drift from the model. This approach is usually followed for 
            assimilation purposes, but should also be useful as a validation tool.

            When called with no arguments it uses a input file (icedrift.in), 
            an example can be found in the "Input" directory

            Call routine with "-help" for some info

gen_icedrift_ens.sh : Wrapper around icedrift2 to calculate icedrift for a model
            ensemble. Uses the CERSAT approach

Drift is calculated using a Runge-kutta 2nd order approach
TODO: A clean-up would be nice

NB: Some matlab diag scripts are available in Diag_Tools directory