Rofi spread

[anton-seaice]

This change allows for spreading of the iceberg melt field according to a climatological pattern.

A new configuration parameter is added, rof2ocn_ice_spread - which is the filename for a netcdf file with a 12-monthly climatological spreading pattern. If this parameter is not set - there is no change to existing behaviour (see repro test)

When a file is provided, the incoming Forr_rofi field is spread according to the pattern supplied in the climatology of spreading.

e.g., for January:

and for June:

Water volume is maintained between that coming from drof and ficeberg in MOM:

See example OM3 100km configuration:

ACCESS-NRI/access-om3-configs@3169a38

[anton-seaice]

mediator timestamps are a bit strange, hence the minor difference in mediator vs mom runoff plots:

[aekiss]

Thanks @anton-seaice - do you think this is ready for the next 25km IAF test run?

[anton-seaice]

Ready from my perspective.

1. Do we want to seperate the impact of changing the land mask in the poles to support b-grid advection from this change ?
2. Needs review and deployment - would take a few days at least

[anton-seaice]

There isn't much flexibility in the mediator io. I modified this so that it can read 3d variable (x,y,time) from a netcdf . For whatever reason, 3d information in restart files is saved in separate 2d variables so the functionality didn't exisit.

[anton-seaice]

I did some cleanup, but have finished that for now