part of cam6_4_033: Wrap MPAS longitude values to [0,2pi) range

doc/ChangeLog

@@ -1,5 +1,69 @@
 ===============================================================
 
+Tag name:
+Originator(s): gdicker
+Date: Jul 18, 2024
+One-line Summary: Address run failures due to MPAS-A longitudes
+Github PR URL: https://github.com/ESCOMP/CAM/pull/1095
+
+Purpose of changes (include the issue number and title text for each relevant GitHub issue):
+ - Wrap MPAS-A longitudes to [0,2pi) range: https://github.com/ESCOMP/CAM/issues/1094
+
+Describe any changes made to build system: N/A
+
+Describe any changes made to the namelist: N/A
+
+List any changes to the defaults for the boundary datasets: N/A
+
+Describe any substantial timing or memory changes: N/A
+
+Code reviewed by:
+
+List all files eliminated: N/A
+
+List all files added and what they do: N/A
+
+List all existing files that have been modified, and describe the changes:
+M       src/dynamics/mpas/driver/cam_mpas_subdriver.F90
+ - Modifies cam_mpas_read_static to ensure lonCell values are in [0,2pi) range
+
+If there were any failures reported from running test_driver.sh on any test
+platform, and checkin with these failures has been OK'd by the gatekeeper,
+then copy the lines from the td.*.status files for the failed tests to the
+appropriate machine below.  All failed tests must be justified.
+
+derecho/intel/aux_cam:
+
+izumi/nag/aux_cam:
+
+izumi/gnu/aux_cam:
+
+CAM tag used for the baseline comparison tests if different than previous
+tag:
+
+Summarize any changes to answers, i.e.,
+- what code configurations:
+- what platforms/compilers:
+- nature of change (roundoff; larger than roundoff but same climate; new
+  climate):
+
+If bitwise differences were observed, how did you show they were no worse
+than roundoff?
+
+If this tag changes climate describe the run(s) done to evaluate the new
+climate in enough detail that it(they) could be reproduced, i.e.,
+- source tag (all code used must be in the repository):
+- platform/compilers:
+- configure commandline:
+- build-namelist command (or complete namelist):
+- MSS location of output:
+
+MSS location of control simulations used to validate new climate:
+
+URL for AMWG diagnostics output used to validate new climate:
+
+===============================================================
+
 Tag name: cam6_3_148
 Originator(s): brianpm, courtneyp, eaton
 Date: Wed 21 Feb 2024

src/dynamics/mpas/driver/cam_mpas_subdriver.F90

@@ -884,15 +884,16 @@ subroutine cam_mpas_read_static(fh_ini, endrun)
 
        use pio, only : file_desc_t
 
-       use mpas_kind_types, only : StrKIND
+       use mpas_kind_types, only : StrKIND, RKIND
        use mpas_io_streams, only : MPAS_createStream, MPAS_closeStream, MPAS_streamAddField, MPAS_readStream
        use mpas_derived_types, only : MPAS_IO_READ, MPAS_IO_NETCDF, MPAS_Stream_type, MPAS_pool_type, &
                                       field0DReal, field1DReal, field2DReal, field3DReal, field1DInteger, field2DInteger, &
                                       MPAS_STREAM_NOERR
        use mpas_pool_routines, only : MPAS_pool_get_subpool, MPAS_pool_get_field, MPAS_pool_create_pool, MPAS_pool_destroy_pool, &
-                                      MPAS_pool_add_config
+                                      MPAS_pool_add_config, MPAS_pool_get_dimension, MPAS_pool_get_array
        use mpas_dmpar, only : MPAS_dmpar_exch_halo_field
        use mpas_stream_manager, only : postread_reindex
+       use mpas_constants, only : pii
 
        ! Arguments
        type (file_desc_t), pointer :: fh_ini
@@ -929,8 +930,13 @@ subroutine cam_mpas_read_static(fh_ini, endrun)
 
        type (MPAS_Stream_type) :: mesh_stream
 
+       integer, pointer :: nCells
+       real(kind=RKIND), dimension(:), pointer :: lonCell_arr
+
        nullify(cell_gradient_coef_x)
        nullify(cell_gradient_coef_y)
+       nullify(nCells)
+       nullify(lonCell_arr)
 
        call MPAS_createStream(mesh_stream, domain_ptr % ioContext, 'not_used', MPAS_IO_NETCDF, MPAS_IO_READ, &
                               pio_file_desc=fh_ini, ierr=ierr)
@@ -1171,6 +1177,12 @@ subroutine cam_mpas_read_static(fh_ini, endrun)
            call endrun(subname//': FATAL: Failed to close static input stream.')
        end if
 
+       call mpas_pool_get_dimension(meshPool, 'nCells', nCells)
+       call mpas_pool_get_array(meshPool, 'lonCell', lonCell_arr)
+
+       ! Ensure longitudes w/i [0, 2*pi) range
+       lonCell_arr(:) = lonCell_arr(:) - (2.*pii) * floor(lonCell_arr(:) / (2.*pii))
+
        !
        ! Perform halo updates for all decomposed fields (i.e., fields with
        ! an outermost dimension of nCells, nVertices, or nEdges)