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#1304 ([TOP/PISCES] p4zbio.F90: tra correction for negative tracers concentration) – NEMO

Opened 8 years ago

Closed 7 years ago

Last modified 6 years ago

#1304 closed Bug (fixed)

[TOP/PISCES] p4zbio.F90: tra correction for negative tracers concentration

Reported by: oriche Owned by: nemo
Priority: low Milestone:
Component: TOP Version: v3.4
Severity: Keywords: PISCES
Cc: oriche@…



While looking through this part of the code with some colleagues we found that there were some inconsistencies.

The block I am referring to is in TOP/PISCES/(P4Z)/p4zbio.F90:

94 xnegtr(:,:,:) = 1.e0
95 DO jn = jp_pcs0, jp_pcs1
96 DO jk = 1, jpk
97 DO jj = 1, jpj
98 DO ji = 1, jpi
99 IF( ( trn(ji,jj,jk,jn) + tra(ji,jj,jk,jn) ) < 0.e0 ) THEN
100 ztra = ABS( trn(ji,jj,jk,jn) ) / ( ABS( tra(ji,jj,jk,jn) ) + rtrn )
102 xnegtr(ji,jj,jk) = MIN( xnegtr(ji,jj,jk), ztra )
104 END DO
105 END DO
106 END DO
107 END DO
108 ! ! where at least 1 tracer concentration becomes negative
109 ! !
110 DO jn = jp_pcs0, jp_pcs1
111 trn(:,:,:,jn) = trn(:,:,:,jn) + xnegtr(:,:,:) * tra(:,:,:,jn)
112 END DO

xnegtr is looping through all the tracers (lines 95-107), but only the values for the last updated tracers are used (lines 110-112) since it has only 3 dimensions.

Line 111 should be in the jn loop (lines 95-107) as well as line 94 (xnegtr initialization to 1).
With the last modification line 102 does not seem necessary.

I think this bug has been carried out since version 3.4 (the version we are using) to the lastest version (the copy/paste is directly from


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Change History (4)

comment:1 Changed 7 years ago by cetlod

Not really a bug. The loop is done through all the tracers to keep mass conservation

comment:2 Changed 7 years ago by cetlod

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

comment:3 Changed 6 years ago by nicolasmartin

  • Keywords PISCES added; p4zbio.F90 removed

comment:4 Changed 6 years ago by nicolasmartin

  • Keywords xnegtr removed
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