Parameter control and objective trade-offs for VIC evapotranspiration

Determine whether the active VIC parameters govern evaporative partitioning and whether a discharge-dominated calibration objective should be traded against the evapotranspiration objective when calibrating the Xixian catchment.

Background

The VIC formulation successfully calibrated discharge but failed the declared evapotranspiration acceptance criteria. This result leaves unresolved whether the selected active parameters can control the relevant evaporative processes.

It also leaves unresolved whether the objective emphasizing discharge should be reformulated as an explicit trade-off with evapotranspiration, rather than allowing discharge performance to dominate the calibration.

References

For VIC, the questions are whether a monthly gridded evapotranspiration product constrains a catchment of about 10,000 km² at the resolution of the model, whether the active parameters govern the evaporative partition, and whether a discharge-dominated objective should trade against it;

— Delegating Earth science model calibration to knowledge-guided LLM agents  (2610.18378 - Zhu et al., 13 Oct 2026) in Section 4, Discussion and conclusion