08 eq_Taux_sea_cycle uses OBS6 data from kj13

[rbeucher]

Going through the notebook I noticed that it uses ERA5-Interm data from kj13.
NCI has ERA-Interim data and we should be able to support without going through the trouble of Tier3.

[flicj191]

Checking the other datasets that were cmorised for this, NCEP and 20CR-V2 come out the same and isn't smooth which comes out in the maps too.

from notebook 4

from notebook 8

[rbeucher]

It would be helpful to determine if this is a data issue. If so, there may not be much we can do about it.