= Name and subject of the action

Last edition: '''[[Wikinfo(changed_ts)]]''' by '''[[Wikinfo(changed_by)]]'''

The PI is responsible to closely follow the progress of the action, 
and especially to contact NEMO project manager if 
the delay on preview (or review) are longer than the 2 weeks expected.

[[PageOutline(2, , inline)]]

== Summary

||=Action       || Validation of the TOP Antarctic Ice Sheet Tracer Module ||
||=PI(S)        || Person R.                                                 ||
||=Digest       || Validation of AIS iron source in eORCA1     ||
||=Dependencies || If any                                                ||
||=Branch       || source:/NEMO/branches/{YEAR}/dev_r{REV}_{ACTION_NAME} ||
||=Previewer(s) || O. Aumont, C. Ethé                                                 ||
||=Reviewer(s)  || O. Aumont, C. Ethé                                                 ||
||=Ticket       || #2656                                                 ||

=== Description
- NEMO trunk rev: 14723
- Configuration : eORCA1

Validation of the TOP trcais.F90 module for representing the external source of biogeochemical tracers from icebergs and ice shelves, currently active for dissolved Fe.

The validation consists of activating the AIS source of Fe in namelist TOP with open and non-open ice shelf cavities in eORCA1 configuration grid and comparing the results with the respective control experiment, i.e., with open or non-open ice shelf cavities (CTL_CAV and CTL_PAR, respectively), in which the external source of Fe is not activated.\\

Each experiment have a duration of 10 years.

=== Implementation

{{{#!box width=35em help
Describe flow chart of the changes in the code. \\
List the Fortran modules and subroutines to be created/edited/deleted. \\
Detailed list of new variables to be defined (including namelists), \\
give for each the chosen name and description wrt coding rules.
}}}

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=== Documentation updates

{{{#!box width=55em help
Using previous parts, define the main changes to be done in the NEMO literature 
(manuals, guide, web pages, …).
}}}

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== Preview 

{{{#!box width=50em info
[[Include(wiki:Developers/DevProcess#preview_)]]
}}}

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== Tests
Results of the validation experiments:\\
See attached plots of surface Fe anomalies (relative to CTLs) for resolved (Fig.1.2) and parameterized (Fig.2.2) ice shelf cavities (Fig.1 and Fig.2 are wrong but don't know how to removed them from the wiki page) when activating Fe input from the Antarctic Ice Sheet (nn_ais_tr = 1, prescribed tracer concentration in iceberg and ice shelf). \\
- The addition of Fe from the AIS in both ice shelf cavity cases results as expected in a net positive effect on surface Fe concentrations relative to CTLs.\\
- Fig.3 shows the surface Fe anomalies when the AIS Fe source is activated between the open and non-open cavity experiments. This illustrates the potential impacts that seawater circulation in ice shelf cavities and Fe inputs associated with this circulation as well as direct inputs from melting ice shelves could have on surface Fe concentrations in the Southern Ocean. However, the seawater properties with open ice shelf cavities have not been initialised correctly for T, S and nutrients. A run should be performed once the initial condition files in the cavities are constructed (see work by K. Hutchinson).

The model outputs are available on jeanzay (idris)
- CTL_PAR run : /gpfsstore/rech/omr/romr014/IGCM_OUT/NEMO/DEVT/clim/eOR1Si3Pv4-CLIM-CORE-CTL
- CTL_CAV run: /gpfsstore/rech/omr/romr014/IGCM_OUT/NEMO/DEVT/clim/eOR1Si3Pv4-CTL-CAV/
- ice shelf cavities parametrized (nn_ais_tr = 1):  /gpfsstore/rech/omr/romr014/IGCM_OUT/NEMO/DEVT/clim/eOR1Si3Pv4-AISFe-PAR1
- ice shelf cavities resolved (nn_ais_tr = 1): /gpfsstore/rech/omr/romr014/IGCM_OUT/NEMO/DEVT/clim/eOR1Si3Pv4-AISFe-CAV1

== Review

{{{#!box width=50em info
[[Include(wiki:Developers/DevProcess#review)]]
}}}

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