The snow depletion parameters (mfsno and scffac) in the IMS converted are derived from an older version of Noah-MP, with the mfsno limitted to 3.0 (to prevent excessively high snow density from developing).
However, the model parameters were updated in late 2022 to newer values from NCAR.
This discrepancy exists in v17.
In theory we should make these consistent by updating the DA code to use the same values as the model. In practice, the NCAR table has many high mfsno values, which will likely result in the DA causing unrealistically high snow density.
The snow depletion parameters (mfsno and scffac) in the IMS converted are derived from an older version of Noah-MP, with the mfsno limitted to 3.0 (to prevent excessively high snow density from developing).
However, the model parameters were updated in late 2022 to newer values from NCAR.
This discrepancy exists in v17.
In theory we should make these consistent by updating the DA code to use the same values as the model. In practice, the NCAR table has many high mfsno values, which will likely result in the DA causing unrealistically high snow density.