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Rotation of the WRF velocity field

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New member
Hi all,
we are currently working on coupling WRF moded with NEMO ocean model and we are fighting with a crucial doubt. here it is:
if we choose "mercator" projection into the WRF code, the OUTPUT FIELDS are still provided on the computational grid (thus the Mercator one) or are they rotated and given in regular spheric coordinates lat-lon?
The variable XLAT and XLONG we read in the output files seem to indicate the output fields relate to the regular spheric coordinates instead of the computational grid...
The documentations we read does not clarify this doubt but it is crucial for the coupling
Thanks for any help
The wind fields (U and V) in wrfout files are grid-relative, which means that they need to be rotated to earth-relative before you use them to drive NEMO ocean model.
XLAT and XLONG are lat/lon in the regular spheric coordinates, and they can be used directly.