Gary,
The MOC variable in CESM output is five dimensional. The MOC metadata
from an ncdump on a file of mine is:
float MOC(time, transport_reg, moc_comp, moc_z, lat_aux_grid) ;
MOC:long_name = "Meridional Overturning Circulation" ;
MOC:units = "Sverdrups" ;
MOC:coordinates = "lat_aux_grid moc_z moc_components
transport_region time" ;
MOC:_FillValue = 9.96921e+36f ;
MOC:missing_value = 9.96921e+36f ;
From right to left, the dimensions are:
latitude
depth
component of velocity used in MOC computation
Eulerian Mean
Eddy-Induced (bolus)
Submeso
spatial region used in MOC computation
Global Ocean - Marginal Seas
Atlantic Ocean + Mediterranean Sea + Labrador Sea + GIN Sea +
Arctic Ocean + Hudson Bay time
I do not know what ferret does under the covers for a five dimensional
variable, but I suspect that this is the root of the problem. Perhaps
there is a nf_get_vara call inside ferret that isn't specifying what
to do with the unexpected additional dimensions.
When I have used ferret to examine MOC in the past, I have first used
NCO to extract along the component and region dimensions, as well as
remove the resulting singleton dimensions.
For instance,
ncwa -a moc_comp,transport_reg \
-d moc_comp,0 -d transport_reg,1 \
-v MOC infile.nc outfile.nc
will extract the Eulerian Mean MOC for the Atlantic etc. region.
Because MOC in the resulting file is now three dimensional, in COARDS
order, ferret can handle it without any problem.
Using ncwa is rather heavy handed. I wouldn't be surprised if there is
a different more elegant work around.
Keith
******************************************************************
Keith Lindsay http://www.cgd.ucar.edu/oce/klindsay/
email: klindsay@xxxxxxxx phone: 303-497-1722 fax: 303-497-1700