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2016WP/2016SharedActions/Workshop_NEMO_in_CMIP6 – NEMO

Version 36 (modified by clevy, 8 years ago) (diff)


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Workshop to analyse and discuss the preliminary results of NEMO in CMIP6 - 28 & 29 January 2016 in Grenoble - France

Organizer: NEMO System Team


All the groups involved in the CMIP6 experiments are now setting up and testing their configurations (ESM or forced ocean in OCMIP). For those using NEMO or part of it as ocean, sea-ice and or biogeochemical component, it appears to be useful to share the analysis of their preparatory simulations in order to identify the robust results, the weaknesses and possible improvements.


Comparing results of NEMO in mainly 2 different global resolutions in different experiments, i.e forced or coupled with different atmospheric models can allow us to better understand and hopefully correct some biais by discriminating the adjustments of the coupled mode from the internal errors of the ocean model.

NEMO configurations in play :

All groups are expected to be using nemo.v3_6_STABLE version of the platform. The configurations should be the ones used in CMIP6. The list below describes geographical extension and model resolution. All combination of NEMO components: dynamics, with or without NEMO sea-ice (LIM) or biogeochemistry(PISCES) are welcome.
ORCA1, ORCA025, …?

Invited groups

In order to facilitate extensive discussions on strengths and weaknesses of the results, we propose not to open the meeting widely, but to decide the list of invited groups.
First mail sent to:

Group Name(s) of contact
CERFACS Laurent Terray, Rym Msadek
CMCC Dorotea Iovino
CNRM Matthieu Chevallier
EC-EARTH Laurent Brodeau
IPSL Julie Deshayes, Martin Vancopenolle
Kiel Arne Biastoch
Met Office & UKESM Colin Jones

Proposed agenda (first draft, waiting for your inputs!)

Meeting will start right after the end of DRAKKAR meeting (i.e. 28 January, or 27 afternoon, maybe), and end 29 at lunchtime at the latest).
A 1.5 / 2 days meeting is suggested, in order to have time to share and discuss the results. Meeting should take place after preliminary analysis of a first set of experiments going on now, but earlier enough for each group to take benefits of discussions for the CMIP6 experiments. Agenda of the meeting should also be discussed: sessions by configuration, by MIP, by open questions (for example: adjustment of vertical parametrization in coupled mode, or coupling frequency...).
Prerequisite is to have the list of experiments available prior to the meeting (see below).

List of subjects to discuss (more soon with your feedbacks):

The following list concerns ORCA1 in forced and coupled mode, and ORCA025 if available

Discussion of scientific results: good news and disappointing results. Discuss ideas for improvements

  • Dense water formation / ventilation in Southern Ocean : comparison to observations ? impact of freshwater fluxes ? contribution of sea-ice ? impact of bathymetry ?
  • Dense water formation / ventilation in North Atlantic : comparison to observations ? contribution of sea-ice ? impact of bathymetry at Greenland-Scotland sills ?
  • Representation of western boundary currents, different choices for viscosity (inc. Smagorinsky) and lateral friction (free slip, no slip...)
  • Representation of unresolved processes (GM, stochastic param., Fox-Kemper)
  • How to close the budgets of heat and freshwater in coupled configurations (inc. routing precipitations over continents into ocean freshwater inputs) ?

Other issues:

  • Issues on the coupling via OASIS-MCT
  • NEMO 3_6_STABLE outputs vs CMIP6 OMDP recommendations (horizontal interpolation, temporal average of z* variables - velocities vs transports)
  • implementation of CMIP6 diagnostics in NEMO

Plans for future tests and eventually date of next meeting

Practical informations

Meeting will take place Thursday 28 january 2016 and Friday morning (up to 1:00 p.m. at the latest) in Grenoble at Maison Jean Kuntzmann (MJK) Amphitheater, Saint Martin d'Hères Campus, Grenoble

Getting to the Maison Jean Kuntzmann Amphitheater

Tram:The Jean Kuntzmann amphitheater is 100 meters away from the "Bibliotheques Universitaires" tramway stop (map).
To get there, take the Tramway line "B" (in green on general map towards Gières - Plaine des Sports Get off the tram at Bibliotheques Universitaires stop.
The ride is approximately 22 minutes from the train station. For reference, the train station is located at the Gares stop and Grenoble city center is located between the Victor-Hugo and Sainte-Claire Les Halles stops.

List of participants

Family Name First name Institution email
Levy Claire CNRS - NEMO System Team Claire.Levy@…
Brodeau Laurent EC-Earth / Stockholm Uni brodeau@…
Chevallier Matthieu CNRM matthieu.chevallier@…
Deshayes Julie IPSL julie.deshayes@…
Uotila Petteri EC-Earth / FMI petteri.uotila@…
Voldoire Aurore CNRM aurore.voldoire@…
Marti Olivier IPSL olivier.marti@…
Jones Colin NERC/Leeds University colin.jones@…
Kuhlbrodt Till NERC/Reading University t.kuhlbrodt@…
Palmieri Julien NERC/NOC julien.palmieri@…
Hewitt Helene Met Office helene.hewitt@…
Storkey Dave Met Office dave.storkey@…
Mathiot Pierre Met Office pierre.mathiot@…
Hyder Pat Met Office patrick.hyder@…
Biastoch Arne GEOMAR abiastoch@…
Msadek Rym CERFACS msadek@…
Prodhomme Chloé BSC-CNS chloe.prodhomme@…

Detailed list of experiments in discussion

Institution/Name? of PI Components in play (ORCA1 or ORCA025,
Forced (which forcing), or coupled (which atmosphere)
Specific options if different from shaconemo Duration of experiment (years) Comments
IPSL ORCA1 LIM3 PISCES Coupled with LMDZ Model still to be tuned. Ocean options kept as close as possible from Shaconemo IPSL base version for CMIP6
Met Office/NERC eORCA025 CICE Coupled to UM Ocean/ice configuration defined as GO6+GSI8. Limited tuning. Ocean/ice component of HadGEM3 GC3 - physical model for UKESM. Met Office/UK contribution to CMIP6
Met Office/NERC eORCA1 CICE MEDUSA Coupled to UM Ocean/ice configuration intended to be traceable to ORCA025 GO6. Some tuning possible Basis for UKESM mid 2016-end 2017. UK contribution to CMIP6 (including OMIP). Ice shelf parameterisation/ice cavities open?
Met Office/NERC eORCA025 CICE MEDUSA coupled to UM Expected to be GO6 as above. Use DEGRAD for BGC UKESM 2018 onwards. Physical model GC3. UK contribution to CMIP6 (including OMIP). Ice cavities open?
GEOMAR ORCA025 LIM2 Spatial GM OMIP period Contribution to OMIP
CNRM/CERFACS eORCA025/ORCA025 LIM3 forced run with CORE-II (IAF) and DFS5 CORE: 1948-2007; DFS5: 1958-2012 NEMO_v3_6_STABLE
IPSL-LOCEAN / Deshayes-Aumont eORCA1 LIM3 PISCES forced by CORE2, climato and interannual 60 yr - 500 yr (climato) still under evaluation / tuning
IPSL-LGGE / Deshayes-LeSommer eORCA025 LIM3 forced by DFS, CORE2 interannual few years only still under development