= 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       || extend the range of options for calculating the horizontal pressure force (IMMERSE action) ||
||=PI(S)        || Mike Bell, Amy Young                                                 ||
||=Digest       || extend the range of options for calculating the horizontal pressure force using line (Shchepetkin & McWilliams 2003) or area integrals (Lin 1997) and finite volume higher order methods  (Engwirda et al. 2017).      ||
||=Dependencies || None                                                ||
||=Branch       || source:/NEMO/branches/{YEAR}/dev_r{REV}_{ACTION_NAME} ||
||=Previewer(s) || Dave Storkey                                                 ||
||=Reviewer(s)  || Dave Storkey                                                 ||
||=Ticket       || #XXXX                                                 ||

=== Description

{{{#!box width=25em help
Will attach pdf files in future. Code is expected to be submitted in 2020. Further developments in future years are likely to be needed.  
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=== 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

{{{#!box width=50em info

[[Include(wiki:Developers/DevProcess#tests)]]
}}}

These developments will be assessed using the idealised seamount configuration introduced by Beckmann & Haidvogel (1993).  This is a standard, widely used test case for evaluating the performance of hpg calculations.  It consists of a Gaussian bump bathymetry initialised with the flow at rest, and an expontential vertical density perturbation profile.
These developments should introduce no change to results unless the new hpg options are activated.
If activated, the new schemes should result in a reduction of spurious currents in regions of sloping bathymetry when using terrain following coordinates (sco).
The test configuration requires a bespoke set of MY_SRC files, a modification to the eosbn2.F90 module, and several namelist parameters.  This configuration currently exists as a UKMO branch from r4.0.2 (http://forge.ipsl.jussieu.fr/nemo/browser/NEMO/branches/UKMO/NEMO_4.0.2_SEAMOUNT) though does not yet run on multiple processors.
There is no obvious single verification value.  Ideally, the result would be a reduction in error with respect to the standard sco formulation.  This may be defined in terms of a reduction in the maximum error (i.e. |umax_new| < |umax_sco|) or it may be a reduction in the time integrated value.  Depending on the scheme in question, there may also be results which should be identically zero.

== Review

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

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