Opened 11 years ago

Closed 11 years ago

Last modified 3 years ago

#646 closed Bug (invalid)

coriolis parameter in limrhg_2.F90

Reported by: dupontf Owned by: nemo
Priority: low Milestone:
Component: LIM2 Version: release-3.2
Severity: Keywords: LIM*
Cc:

Description

Hi all,

I fear that C-grid and B-grid may have bumped into each other at line 178 of limrhg_2.F90. The old code has

zcorl(ji,jj) = zmass(ji,jj) * fcor(ji,jj)

which seems reasonable from a B-grid perspective (U/V collocated) but the new code has

zcorl(ji,jj) = zmass(ji,jj) &

& *( fcor(ji,jj ) * wght(ji,jj,2,2) + fcor(ji-1,jj )*wght(ji,jj,1,2) &
& + fcor(ji,jj-1) * wght(ji,jj,2,1) + fcor(ji-1,jj-1)*wght(ji,jj,1,1) ) * zusw

which seems to be C-grid. However, LIM2 is still B-grid right?

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Change History (4)

comment:1 Changed 11 years ago by rblod

Hi Fred

Indeed LIM2 is still in B grid. It seems to me that fcor is initialized at a T point in limmsh_2, and that's why we're putting it back on a UV point. It would have been more appropriate to have it directly on UV point from the ocean value of ff, I guess the reasons are historical.

Rachid

comment:2 Changed 11 years ago by dupontf

Thanks a lot Rachid for your explanations.

I should have checked limmsh_2.F90 first. I can see that NEMO3.1 and NEMO3.2 have the same coriolis definition based on gphit (T-point indeed) but only NEMO3.2 recomputes the coriolis parameter at B-ice points. So it was actually a (minor) bug in NEMO3.1. I guess you can remove my ticket!

Fred.

comment:3 Changed 11 years ago by dupontf

  • Resolution set to invalid
  • Status changed from new to closed

comment:4 Changed 3 years ago by nemo

  • Keywords LIM* added
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