MOM6 iau increment is "broken"

[guillaumevernieres]

Looks like somebody's pythonification of the bash function that converted the soca increment to the MOM6 iau increment didn't got to well:

12: NOTE from PE     0: updating fields with increments ncount:        1.
12: NOTE from PE     0: updating fields with weight inc_wt:0.50000000
12:
12: FATAL from PE     0:  Could not find target coordinate   1020.84301757812      in get_polynomial_coordinate. This is caused by an inconsistent interpolant (perhaps not monotonically increasing):   1020.843017578\
12                          NaN                     NaN
12: