Wrong logical used in IF statement for tracer trends in traldf_iso

[timgraham]

Context

In the case where Active tracer trends are requested but passive tracer trends are not we are seeing a lot of "You should not have seen this print" type error messages in the output file. These originate from TRA/traldf_iso.F90

Analysis

In the IF statement at line 333 l_trdtra is used with cdtype == "TRC". This eventually causes trd_trc to be called even though key_trdtrc is not defined.

         IF( l_trdtra .AND. cdtype == "TRC" )   THEN      ! save the horizontal component of diffusive trends for further diagnostics
            CALL trd_tra( kt, cdtype, jn, jptra_iso_x, ztrax )
            CALL trd_tra( kt, cdtype, jn, jptra_iso_y, ztray )
            CALL trd_tra( kt, cdtype, jn, jptra_iso_z1, ztraz )  ! This is the first part of the vertical component.
         ENDIF

Recommendation

Replace l_trdtra with l_trdtrc in this IF block.

[timgraham]

Closing as this is an error in a Met Office branch (not v3.6 Stable)