Hi all,
Over the next few years, we may wish to start developing coupled models with AGRIF nests. Can I confirm that at the moment, this is only possible at the parent grid level (i.e. the atmosphere doesn’t see the high resolution information?).
If this is the case, we have the possibility to include development work for coupling at the child grid level in an upcoming grant application. I’d be interested to know if you think this is feasible and if it’s something that the NEMO community would be interested in having on the trunk.
Thanks,
Tim
No, 
You can couple all the child domains you want as soon as the coupling interface of your atmosphere is able to send/receive a field to/from different instances of the ocean, e.g. the SST sent by NEMO parent and the child grids. OASIS will interpolate the SST from NEMO parent and child grids onto the atmospheric grid and next the atmospheric model will need to be merge these 2 received fields into a single array. Note that you could also imagine the SST send by N NEMO running in parallel as an ensemble oceanic run.
Symmetrically, you can also in NEMO send/receive a field to/from different instances of the atmosphere, e.g. if your atmospheric model contains nested zooms (typically WRF).
Note that this functionality was alreay existing in 4.0.
In NEMO, this is coded in cpl_oasis3.F90, look forkey_agrif. Coupling with different instances of the atmosphere is done trough the use of ncplmodel and a coupling mask in cpl_rcv. The section 4 of this paper could help you to understand what is done in NEMO (and should also be done in the atmosphere).
Sébastien
Thanks Seb. That’s really useful information and makes things much simpler for us to define what development is needed (i.e. it’s in our own atmosphere model rather than NEMO)