Variational rv/rh in BUMP

Current BUMP seems only support constant length scale for 3D-Var, or one value for RH or RV over the whole domain. Is there any way to have region-dependence B-matrix in BUMP, including urban/rural difference etc? Thanks

Hi @ytangnoaa. Absolutely, the current implementation supports two streams for input rh/rv:

  • In the bump section of the yaml file, you can specify a value per variable or a value per variable and level for rh and rv (example here).
  • In the input section of the yaml file, you can provide paths of files containing values of rh and rv, for instance here. These files have the same format as other files containing a model state (thus, they are model-specific). They can be produced in a previous diagnostic step with BUMP (example here), or created manually with any other software.

Thank you for this information. These yaml files are in the FV3-JEDI testinput folder. However, the ctest file does not include them, and the required model files are not there. How can I download and try it?

The staticb_[...] tests are included in the tier 2 of FV3-JEDI tests (more expensive ones). To run them, you need to set the environment variable:


and then rebuild your bundle (simply do a touch on a CMakeLists.txt file and recompile). You should see the new tests when running ctest -N.

Thank you. It outputs the nicas_norm file based on

How can I apply this nicas_norm file in 3D-Var DA?