= More realistic air-ice/snow turbulent flux estimates over sea-ice

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.

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== Summary ==

||=Action       || More realistic air-ice/snow turbulent flux estimates over sea-ice ||
||=PI(S)        || Laurent Brodeau @ Ocean Next ||
||=Digest       || Implementation of a bulk-transfer-coefficient parameterization for sea-ice-covered regions. This parameterization should consider sea-ice roughness and be able to handle extremely stable surface atmospheric layer conditions typical of sea-ice-covered regions. ||
||=Dependencies || no                                            ||
||=Branch       || source:/NEMO/branches/{YEAR}/dev_r{REV}_{ACTION_NAME} ||
||=Previewer(s) || Names                                                 ||
||=Reviewer(s)  || Names                                                 ||
||=Ticket       || #2369                                                 ||

=== Description ===

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=== Implementation

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=== Documentation updates ===

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Using previous parts, define the main changes to be done in the NEMO literature 
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== Preview 

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== Tests

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Test-case associated with this development:

	• Test case name: '''STATION_ASF''' (C1D meets SAS). See [https://github.com/NEMO-ocean/NEMO-examples/tree/master/STATION_ASF] for a more complete introduction.

	• Test case functionality: test-case STATION_ASF checks that all bulk algorithms available in NEMO, used to estimate the bulk transfer coefficient for turbulent air-sea and air-ice fluxes, are working properly. This is done by checking that all turbulent fluxes computed at the punctual location of STATION_ASF lie within a reasonable range.


	• Test case setup: in STATION_ASF nemo.exe runs on one processor and needs only 2 lightweight netCDF files as input. These 2 files provide hourly time-series of sea-surface variables (SST, SSH), and surface atmospheric state (wind, temperature, humidity and downwelling radiative fluxes), respectively, at the punctual location of STATION_ASF. 1 year of simulation with STATION_ASF takes a few tens of seconds on 1 proc.

	• Test case verification value: WILL BE boolean. Each computed turbulent flux (hourly time-series), namely evaporation, wind stress and sensible flux, will be checked for consistency during a whole year. This operation will be carried out with every bulk (air-sea and air-ice) parameterization algorithms available in NEMO, including the testing of different options: cool-skin/warm-layer and wave-pattern input).


	• Status of the test case as for now: Exists on the official GitHub for NEMO. Boolean output not ready yet, version for air-ice fluxes in progress. 







== Review

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