Checking Atmospheric Forcing

Checking Atmospheric Forcing#

Overview#

The check_forcing.py script validates eCLM atmospheric forcing files specified in datm_in namelist and stream files. It checks for file existence, required variables as specified in the stream files, and validates that radiation and precipitation values are non-negative.

Requirements#

pip install f90nml lxml netCDF4 numpy

Basic Usage#

# Check forcing files (output: errors only)
python checkforcing/check_forcing.py /path/to/datm_in

# Verbose output with detailed information
python checkforcing/check_forcing.py /path/to/datm_in -v

# Automatically fix negative values
python checkforcing/check_forcing.py /path/to/datm_in --fix-negative

What It Checks#

  1. Namelist parsing: Validates datm_in and extracts stream file references

  2. Stream file parsing: Reads XML stream files and extracts forcing file paths

  3. File existence: Verifies all referenced forcing files exist

  4. Variable presence: Checks that NetCDF files contain expected variables based on stream mappings

  5. Non-negative validation: Ensures radiation (swdn, lwdn) and precipitation (precn) variables contain no negative values

Variable Mapping#

Stream files define mappings between NetCDF variables (in files) and eCLM variables (used by model):

<variableNames>
  FSDS    swdn     <!-- NetCDF variable FSDS maps to eCLM variable swdn -->
  FLDS    lwdn
  PRECTmms  precn
</variableNames>

Output Modes#

Quiet Mode (default)#

Shows only errors and final status:

✗ 2022-10.nc:
    FSDS (eCLM: swdn): 12/8760 values are negative (min=-0.0034)

✗ Validation failed

Verbose Mode (-v)#

Shows complete information including:

  • Namelist details

  • Stream file contents

  • All forcing files checked

  • Variable mappings

  • Detailed statistics

Fix Mode (--fix-negative)#

Automatically corrects negative values:

  • Sets negative values to zero

  • Updates file history attribute

  • Re-validates after fixing

✓ Fixed 2022-10.nc: FSDS(12)

✓ All checks passed successfully

Exit Codes#

  • 0: All checks passed

  • 1: Validation errors found