Tracer advection model

• Added a tracer advection model based on Lorenz-96 using a Semi-Lagrangian scheme. The lorenz_96_tracer_advection model_mod was implemented by Fairuz Ishraque as part of a SIPaRCS 2021 project.

• Forward operator documentation updated to Manhattan

Bug-fix for fixsystem for NAG compiler

Fix formatting of code blocks used when compiling mpi/null_mpi_utilities_mod.f90 with the NAG compiler.

CM1 and 3D Cartesian location_mod updates

Contributed by Jon Labriola

• Updated CM1 model_mod to use mixed-case boundary conditions, for example
  periodic in the x-direction but non-periodic in the y-direction.
• Added capability to CM1 model_mod to interpolate 3D fields such as reflectivity.
• Added capability to use multiple localization radii to threed_cartisian
  location_mod.
• Bug-fix for threed_cartesian location_mod for periodic boundaries.

CLM Snow Water Equivalent

• Updated Community Land Model (CLM) model_mod, scripting, and diagnostics.
• New capability to repartition snow layer mass and dimension variables.
  The repartitioning ensures that the adjustments applied to the snow layers
  are consistent (mass and dimensions are conserved) with the adjustment of
  the total snow water equivalent.
• New observation converters for NASA_Earthdata and NSIDC
• Support for netcdf _FillValue
• Bug-fix for clm nc_write_model_atts lon vs nlon

bug fix for inf_flavor namelist option

Namelist option inf_flavor reverted to integer only vs. character or integer to conform to Fortran standards.

filter_assim refactor

Refactoring filter assim:

• Each process calculates increments vs. previously only one process would do this for each observation. So more elements in the broadcast/send receive, and redundant (but simultaneous) calculation by each process. This is to allow future implementation of new assimilation algorithms

Code readability changes:

• removed timing variables
• get_close caching moved inside subroutine
• adaptive localization moved into subroutine
• cov_factor and adjust_obs_impact moved into subroutine
• Call new subroutines in adaptive_inflate_mod:
• update_single_state_space_inflation, update_varying_state_space_inflation

Bug fix for groups when used with posterior spatially-varying adaptive inflation

Removed the additional outlier threshold test for each group when using posterior spatially-varying adaptive inflation.
The outlier test is done for the entire ensemble when the posterior forward operators are computed.

CLM Snow Water Equivalent

Added snow repartitioning scheme to CLM-DART. Pre release version.

• Recommended for CLM only. If using other models, please checkout the latest version of DART.
• Uses CLM 5 and CESM 2.2. Not backwards compatible with older versions of CLM.

Improved observation converter documentation

• Improved radar observation converter documentation
• Fixed CHAMP converter links

bug fix for very large models

Bug fixes for models where the number of elements in the state exceeds 2^31-1:

• mpi_utilities_mod using correct check for message length > SNDRCV_MAXSIZE
• new developers test for large message sizes
• State vector IO updated to use i8 for state indexing
• WRF model_mod now using i8