Use input-file units consistently in SIPNET documentation

[dlebauer]

Description

SIPNET input documentation should document units as they are provided by users, rather than units used internally by the model.

Review:

• docs/user-guide/model-inputs.md for climate and event inputs
• docs/parameters.md for sipnet.param parameters

Check the corresponding input parsing code and update documented units to match the input files. Where SIPNET converts units internally, note the conversion only where useful.

For example, precipitation is supplied in mm and converted internally to cm, while vapor pressure is supplied in Pa and converted to kPa.

This is a documentation-only change; do not change model behavior or input formats.

—-

The SIPNET interface functions in the PEcAn repository, convert between PEcAn-standard units (not relevant here) and SIPNET input/output units and can help by providing a secondary source of information ab some of the units in input and output files:

• models/sipnet/R/write.configs.SIPNET.R
• models/sipnet/R/met2model.SIPNET.R
• models/sipnet/R/write.events.SIPNET.R
• models/sipnet/R/model2netcdf.SIPNET.R

If there is a discrepancy, sipnet source code is the authoritative source and there may be a bug in the pecan code; reach out on the pecan slack channel or file an issue in the pecan repository.

[mayur-jangale]

I'd like to work on this issue. I've verified the units discrepancy in docs/user-guide/model-inputs.md against the input parsing code in src/sipnet/sipnet.c. Could I be assigned?

[priyanshusky0]

@dlebauer , I've submitted PR #392 addressing the unit inconsistencies described in this issue. The changes are documentation-only and document the units as they are actually supplied in the SIPNET input files.

While cross-checking the PEcAn SIPNET interface as suggested in this issue, I also noticed a potentially separate issue in models/sipnet/R/write.configs.SIPNET.R around litterInit.

The code currently has:

PEcAn.utils::ud_convert(IC.pools$litter, "g m-2", "g m-2")

However, prepare_pools() documents this return value as kg C/m², while SIPNET expects g m-2. This appears to pass the value through without the required kg-to-g conversion, potentially making litterInit 1000× too small.

The corresponding soilInit conversion does perform the expected kg m-2 -> g m-2 conversion. This seems separate from #390, so I have not included it in PR #392. I can open a separate issue for this if appropriate.

Also, I tried to join the PEcAn Slack community as requested here, but I'm currently unable to join due to an email/account-related issue. Could someone please help me with access or let me know the correct way to join?