RIVER_ROUTING not compatible with cru-ncep forcings > 5.3.2

[fberzaghi]

RIVER_ROUTING only works with cru-ncep v5.3.2 due to a mismatch with the later versions of cru-ncep and the routing maps. This error is triggered if later versions of cru-ncep are used with the trunk versions (I have found this error in 2_1).

Error message

FATAL ERROR FROM ROUTINE routing_linkup
In the routine which make connections between the basins and ensure global coherence, there is a problem with outflow linkup without any valid direction. Try with check=.TRUE (Perhaps there is a problem with the grid.)

Solution: turn off RIVER_ROUTING = N in run.def

[fberzaghi]

PS: river routing is mostly used in finer scale simulations, so if you run at 1-2 degrees you can safely turn it off.

[aducharne]

Réunion du 25/2/20 : ce problème avec CRU-NCEP > v5.3.2 se pose uniquement aux résolutions 1 et 2 degré, et empêche pour l'instant d'utiliser les dernières versiosn de CRU-NCEP à ces résolutions.

Lien probable avec le ticket à ouvrir par F Cheruy sur les pbs de routage en mode zommé.
Voir aussi si lien avec ticket #575, qui relate un pb avec nouveau driver, routage et CRU-NCEP v7.2/twodeg

[jgipsl]

The same problem is seen with forcing CRUJRA/v2.1 in 2deg. See ticket #772

[jgipsl]

Note that the RIVER_ROUTING is now set to n in some default set-up while waiting for a solution of this problem. See [7307].