Tezel et al. (2026) Uncertainty Assessment of the Impacts of Climate Change on Streamflow in the Iznik Lake Watershed, Türkiye

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

Identification

• Journal: Water
• Year: 2026
• Date: 2026-01-10
• Authors: Anıl Çalışkan Tezel, Adem Akpınar, Aslı Bor, Şebnem Elçi
• DOI: 10.3390/w18020187

Research Groups

The paper does not explicitly list specific research groups, labs, or departments involved.

Short Summary

This study investigates the impacts of climate change on river streamflow in the Iznik Lake Watershed, Türkiye, using downscaled climate projections and the SWAT+ hydrological model. It finds varied changes in streamflow, with increased maximum flows and significant uncertainty primarily driven by climate projections and evapotranspiration methods.

Objective

• To investigate the impacts of climate change on river streamflow in the Iznik Lake Watershed, Türkiye, by integrating downscaled climate projections with a hydrological model.
• To quantify the magnitude of climate-induced changes and the relative contribution of climate realizations, emission scenarios, and hydrological parameters to streamflow uncertainty.

Study Configuration

• Spatial Scale: Iznik Lake Watershed, northwestern Türkiye, including Karadere and Findicak sub-catchments.
• Temporal Scale: Near future and far future climate projections.

Methodology and Data

• Models used: SWAT+ hydrological model, downscaled climate projections.
• Data sources: Downscaled climate projections (from four representative grid points), hydrological parameters for SWAT+ model calibration, and observed streamflow data (implied for calibration at Karadere station). Uncertainty analysis employed ANOVA-based approach and Bayesian Model Averaging (BMA).

Main Results

• Climate projections indicate wetter winters and springs but drier summers, accompanied by an overall warming trend in the study area.
• At the Karadere station (main inflow), mean annual streamflow is projected to change from −7% to +56% in the near future and from +19% to +54% in the far future.
• Maximum flows (Qmax) are projected to increase significantly, ranging from +0.9% to +47% in the near future and from +21% to +63% in the far future, indicating higher peak discharges.
• Low-flow conditions, particularly in summer, exhibit the greatest relative variability due to near-zero baseline discharges.
• Relative change analysis revealed heterogeneous hydrological responses within the basin, with considerable differences between the Karadere and Findicak sub-catchments.
• Uncertainty analysis identified climate projections and potential evapotranspiration calculation methods as the dominant influences on streamflow outputs, while land use change contributed negligibly to overall uncertainty.

Contributions

• Provides new hydrological insights for the Iznik Lake Watershed, a critical freshwater resource in northwestern Türkiye, under future climate change scenarios.
• Quantifies the magnitude of projected changes in mean annual, maximum, and low streamflows for the region.
• Systematically assesses and quantifies the relative contributions of different uncertainty sources (climate realizations, emission scenarios, hydrological parameters, evapotranspiration methods, land use change) to streamflow projections using ANOVA and BMA.
• Offers valuable insights for decision-makers in water resource management and future hydrological modeling efforts in the region.

Funding

The paper does not provide specific information regarding funding projects, programs, or reference codes.

Citation

@article{Tezel2026Uncertainty,
  author = {Tezel, Anıl Çalışkan and Akpınar, Adem and Bor, Aslı and Elçi, Şebnem},
  title = {Uncertainty Assessment of the Impacts of Climate Change on Streamflow in the Iznik Lake Watershed, Türkiye},
  journal = {Water},
  year = {2026},
  doi = {10.3390/w18020187},
  url = {https://doi.org/10.3390/w18020187}
}