Crow et al. (2026) Streamflow Calibration in Ungauged Basins Using SWOT Discharge and SMAP Surface Soil Moisture Products

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Water Resources Research
• Year: 2026
• Date: 2026-06-30
• Authors: Wade T. Crow, Michael Durand, Stephen Coss, Rolf Helmut Reichle
• DOI: 10.1029/2025wr041875

Research Groups

• Department of Hydrology, University of Colorado Boulder
• NASA Jet Propulsion Laboratory

Short Summary

This study presents a multi-objective calibration method using satellite remote sensing data to reduce systematic errors in land surface models (LSMs) without relying on in-channel measurements of discharge. The approach combines soil moisture retrievals from SMAP and synthetic Q retrievals designed to mimic SWOT Q products.

Objective

• Investigate the effectiveness of combining multiple calibration constraints for LSMs, including a long-term water balance and synthetic Q retrievals, to reduce systematic errors without relying on in-channel measurements of discharge.

Study Configuration

• Spatial Scale: Medium-scale basins (500–10,000 km^2) in the eastern United States.
• Temporal Scale: Long-term water balance and daily time step for LSM simulations.

Methodology and Data

• Models used: Land surface models (LSMs)
• Data sources:
  • Soil Moisture Active Passive (SMAP) surface soil moisture retrievals
  • Synthetic Q retrievals designed to mimic Surface Water Ocean Topography (SWOT) Q products

Main Results

• Multi-objective calibration using SMAP and synthetic SWOT Q retrievals can simultaneously optimize LSM daily Q bias and precision without relying on in-channel Q measurements.
• The addition of water balance and synthetic SWOT Q constraints is particularly valuable for ensuring LSM Q estimates with low bias in their mean and temporal variability, respectively.

Contributions

• Original value lies in the development of a multi-objective calibration method that leverages satellite remote sensing data to reduce systematic errors in LSMs without relying on in-channel measurements of discharge.
• This approach has the potential to improve the accuracy and reliability of LSM Q estimates in ungauged hydrologic basins.

Funding

• NASA's Terrestrial Hydrology Program (grant number: 80NSSC18K0314)
• National Science Foundation's Division of Earth Sciences (grant number: EAR-1844571)

Citation

@article{Crow2026Streamflow,
  author = {Crow, Wade T. and Durand, Michael and Coss, Stephen and Reichle, Rolf Helmut},
  title = {Streamflow Calibration in Ungauged Basins Using SWOT Discharge and SMAP Surface Soil Moisture Products},
  journal = {Water Resources Research},
  year = {2026},
  doi = {10.1029/2025wr041875},
  url = {https://doi.org/10.1029/2025wr041875}
}