Wang et al. (2026) Revisiting the application of variable infiltration capacity (VIC) model in the Colorado River Basin using SMAP and GRACE

Identification

• Journal: Scientific Reports
• Year: 2026
• Date: 2026-04-03
• Authors: Zhaocheng Wang, Swastik Ghimire, Kristen M. Whitney, Giuseppe Mascaro, Mu Xiao, Haowen Yue, Enrique R. Vivoni
• DOI: 10.1038/s41598-026-47430-9

Research Groups

• School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA
• Center for Hydrologic Innovations, Arizona State University, Tempe, AZ, USA
• NASA Goddard Space Flight Center, Greenbelt, MD, USA
• Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USA
• Scripps Institution of Oceanography, University of California, La Jolla, CA, USA

Short Summary

This study implemented a multi-source calibration and evaluation framework for the Variable Infiltration Capacity (VIC) model in the Colorado River Basin, demonstrating its robust capacity to reproduce spatially distributed hydrologic processes, including soil moisture and terrestrial water storage dynamics, beyond traditional streamflow-only calibration. The enhanced model performance provides increased confidence for water management in the drought-stricken basin.

Objective

• To implement a calibration and multi-source evaluation framework for the Variable Infiltration Capacity (VIC) model in the Colorado River Basin (CRB) using observations from ground snow stations, streamflow records, and satellite missions (SMAP and GRACE).
• To establish the VIC model's capacity to represent subsurface water storage dynamics in different land cover types, thereby enhancing confidence for supporting water management in the CRB.

Study Configuration

• Spatial Scale: Colorado River Basin (CRB), including key sub-basin outlets.
• Temporal Scale: Multi-year evaluation period (specific dates not detailed in abstract).

Methodology and Data

• Models used: Variable Infiltration Capacity (VIC) model.
• Data sources:
  • Ground snow stations (observations)
  • Streamflow records (observations)
  • NASA’s Soil Moisture Active Passive (SMAP) mission (satellite)
  • NASA’s Gravity Recovery and Climate Experiment (GRACE) mission (satellite)
  • Historical meteorological forcing data (PRISM)

Main Results

• The VIC model achieved excellent streamflow performance at key sub-basin outlets in the CRB after calibration with snow and streamflow records (e.g., Nash-Sutcliffe Efficiency of 0.96 in the Upper Basin).
• Independent evaluations with SMAP revealed strong model performance in reproducing surface soil moisture (R² = 0.71) and root-zone soil moisture (R² = 0.81), with systematic elevation-dependent patterns.
• A multi-year evaluation with GRACE demonstrated a robust reproduction of basin-scale terrestrial water storage dynamics and their interannual variability (R² = 0.66–0.86).

Contributions

• Developed and applied a novel multi-source evaluation framework for hydrologic models in the Colorado River Basin, moving beyond traditional streamflow-only calibration.
• Provided enhanced confidence in the VIC model's ability to accurately represent spatially distributed hydrologic processes, particularly subsurface water storage dynamics across various land cover types.
• Offered a more reliable and validated tool for water resource management in the CRB, especially critical under prolonged drought conditions.

Funding

• NASA Applied Sciences program (Award No. 80NSSC22K0925; “Managing the Colorado River as an Infrastructure Asset: Fusing Remote Sensing and Numerical Modeling in the Operations of the Central Arizona Project”).
• Arizona Water Innovation Initiative (AWII), a multi-year partnership with the State of Arizona led by Arizona State University’s Julie Ann Wrigley Global Futures Laboratory in collaboration with the Ira A. Fulton Schools of Engineering.

Citation

@article{Wang2026Revisiting,
  author = {Wang, Zhaocheng and Ghimire, Swastik and Whitney, Kristen M. and Mascaro, Giuseppe and Xiao, Mu and Yue, Haowen and Vivoni, Enrique R.},
  title = {Revisiting the application of variable infiltration capacity (VIC) model in the Colorado River Basin using SMAP and GRACE},
  journal = {Scientific Reports},
  year = {2026},
  doi = {10.1038/s41598-026-47430-9},
  url = {https://doi.org/10.1038/s41598-026-47430-9}
}