[[PageOutline()]] [[TOC(WorkingGroups/top-dg/*, depth=1)]] = '''NEMO v3.6 TOP BDY Patch''' = Last edition: '''[[Wikinfo(changed_ts)]]''' by '''[[Wikinfo(changed_by)]]''' '''BEFORE USE''' : this patch is meant to provide only the core functionality for TOP BDY. Official support for tracers BDY will be given only for versions after NEMO v4.0 . == Description == This patch to enable the core support of BDY for TOP passive tracers with NEMO v3.6 (tested with r10254). Note that in this patch, routines that provide to initialization/reading of Boundary conditions (trcbc.f90) were also updated. ''BDY schemes'' included in this version are the following (see trcbdy.F90): * '''frs''' : Flow Relaxation Scheme * '''specified''' : Specified value * '''neumann''' : Duplicate the value for tracers * '''orlanski''' : Orlanski radiation * '''orlanski_npo''' : Orlanski radiation with adaptive nudging Refer to the BDY description of NEMO manual for further details on the different schemes. In '''namelist_top_ref''' the following changes are necessary (see the patched version contained in the code provided): {{{ !----------------------------------------------------------------------- &namtrc_bc ! cn_dir_sbc = './' ! root directory for the location of SURFACE data files cn_dir_cbc = './' ! root directory for the location of COASTAL data files cn_dir_obc = './' ! root directory for the location of OPEN data files / !---------------------------------------------------------------------- !namtrc_bdy ! Setup of tracer boundary conditions !----------------------------------------------------------------------- $namtrc_bdy cn_trc_dflt = 'neumann' ! OBC applied by default to all tracers cn_trc = 'none' ! Boundary conditions applied to the passive tracers (selected in namtrc) nn_trcdmp_bdy = 0 ! Use damping timescales defined in nambdy of namelist ! = 0 NO damping of tracers at open boudaries ! = 1 Only for tracers forced with external data ! = 2 Damping applied to all tracers / }}} Details on the usage of these namelists and the setup of a one tracer case are given below. == Usage walktrough == Code is contained in the attached tarball and it contains a set of modified files in the classic "MY_SRC" folder to be added in NEMO configuration. Note that '''namelist_top_ref''' has to be modified by the user in /NEMOGCM/CONFIG/SHARED according to the description above (or the sample file provided in the tarball). A modified fortran data structure of namtrc was here developed to set the different boundary conditions of passive tracers, as in the following example : {{{ !----------------------------------------------------------------------- &namtrc ! tracers definition !----------------------------------------------------------------------- ! ! name ! title of the field ! initial data ! initial data ! sbc ! cbc ! obc ! save ! ! ! ! ! units ! from file ! ! ! ! or not ! ! ! ! ! ! or not ! ! ! ! ! sn_tracer(1) = 'TRACER1 ' , 'Tracer1 for key_my_trc ', 'unitless' , .true. , .false. , .true. , .true. , .true. ... / }}} namtrc_bc : here are provided the different boundary conditions for passive tracers, namely surface, coastal, and open lateral boundaries (see the example below for usage). namtrc_bdy : here set the BDY schemes to be used for those tracers that BDY inputs are provided (according to namtrc options)