Yassin et al. (2026) Sensitivity of Large‐Scale Hydrological Predictions to Precipitation Phase Partitioning Methods Under a Changing Climate

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

Identification

• Journal: Hydrological Processes
• Year: 2026
• Date: 2026-06-23
• Authors: Fuad Yassin, John Willard Pomeroy, Alain Pietroniro, Bruce Davison, Mohamed Elshamy, Zelalem K. Tesemma
• DOI: 10.1002/hyp.70608

Research Groups

• University of Saskatchewan Department of Geography
• University of Toronto Department of Civil Engineering
• National Water Research Institute

Short Summary

This study investigates the impact of different precipitation phase-partitioning formulations on hydrological projections in the Saskatchewan River Basin under historical and late-century climate conditions. The results highlight the importance of accurately accounting for precipitation phase-partitioning uncertainty in climate-impact assessments.

Objective

• To quantify the influence of four precipitation phase-partitioning formulations on simulated precipitation phase, snow storage, and streamflow response in the Saskatchewan River Basin.

Study Configuration

• Spatial Scale: Regional scale (Saskatchewan River Basin)
• Temporal Scale: Historical (1981–2010) and late-century (2071–2100) climate conditions

Methodology and Data

• Models used: MESH land-surface hydrological model
• Data sources: CanRCM4 climate projections, observational data for validation

Main Results

• Late-century projections show increases in total precipitation of 19%–30% and declines in snowfall fraction of 25%–34% across landforms.
• Reductions in annual maximum SWE ranged from approximately 5%–13% in the cordillera and foothills to 13%–19% in the plains.
• Inter-method spreads in projected SWE were small in colder landforms (< 4 percentage points) but reached 6–9 percentage points in the plains and lowlands.
• Streamflow timing advanced consistently, with spring pulse onset date advancing by a median of 27 days.

Contributions

• This study highlights the importance of explicitly accounting for precipitation phase-partitioning uncertainty in climate-impact assessments for snow-dominated and mixed-regime river basins.
• The results demonstrate that physically based psychrometric formulations are more robust than empirical temperature-threshold schemes under stronger warming conditions.

Funding

• Natural Sciences and Engineering Research Council (NSERC) of Canada
• Canadian Foundation for Climate and Atmospheric Sciences (CFCAS)
• Saskatchewan Water Security Agency

Citation

@article{Yassin2026Sensitivity,
  author = {Yassin, Fuad and Pomeroy, John Willard and Pietroniro, Alain and Davison, Bruce and Elshamy, Mohamed and Tesemma, Zelalem K.},
  title = {Sensitivity of Large‐Scale Hydrological Predictions to Precipitation Phase Partitioning Methods Under a Changing Climate},
  journal = {Hydrological Processes},
  year = {2026},
  doi = {10.1002/hyp.70608},
  url = {https://doi.org/10.1002/hyp.70608}
}