Calibration using downscaled and bias-corrected satellite soil-moisture data can improve watershed model representation of soil-moisture variability

Asfaw, Binyam Workeye; Maksud, Siam; Fuka, Daniel R.; Collick, Amy S.; White, Robin R.; Easton, Zachary M.

doi:10.5194/hess-30-5999-2026

Articles | Volume 30, issue 18

https://doi.org/10.5194/hess-30-5999-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/hess-30-5999-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 30, issue 18

Research article

|

24 Sep 2026

Research article |

| 24 Sep 2026

Calibration using downscaled and bias-corrected satellite soil-moisture data can improve watershed model representation of soil-moisture variability

Binyam Workeye Asfaw, Siam Maksud, Daniel R. Fuka, Amy S. Collick, Robin R. White, and Zachary M. Easton

Data sets

ASCAT Surface Soil Moisture Climate Data Record v7 12.5\,km sampling -- Metop EUMETSAT H SAF https://doi.org/10.15770/EUM_SAF_H_0009

TopoSWAT Source D. R. Fuka and Z. M. Easton https://doi.org/10.6084/m9.figshare.1342823.v4

SMAP L3 Radiometer Global Daily 36 km EASE-Grid Soil Moisture, Version 5 P. E. O'Neill et al. https://doi.org/10.5067/ZX7YX2Y2LHEB

SMAP Enhanced L3 Radiometer Global and Polar Grid Daily 9 km EASE-Grid Soil Moisture P. E. O'Neill et al. https://doi.org/10.5067/M20OXIZHY3RJ

Short summary

We investigated the use of downscaled and bias-corrected satellite soil‑moisture data to inform hydrologic model calibration beyond traditional streamflow‑based approaches. Incorporating soil moisture improved representation of internal moisture dynamics without degrading streamflow performance. The study illustrates how satellite soil moisture can help constrain hydrologic models while emphasizing the importance of model structure.