Anderson et al. (2025) What is a drought-to-flood transition? Pitfalls and recommendations for defining consecutive hydrological extreme events

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

Identification

• Journal: Repository for Publications and Research Data (ETH Zurich)
• Year: 2025
• Date: 2025-11-07
• Authors: Bailey J. Anderson, Eduardo Muñoz‐Castro, Lena M. Tallaksen, Alessia Matanó, Jonas Götte, Rachael Armitage, Eugene Magee, Manuela Brunner
• DOI: 10.3929/ethz-c-000787656

Research Groups

Information not provided in the given paper text.

Short Summary

This study critically assesses existing methodologies for defining and detecting rapid drought-to-flood transition events, demonstrating that different threshold-level and time-window approaches significantly alter event characteristics and detection rates, often failing to identify historically impactful events.

Objective

• To assess the suitability of and differences between event selection methods applied to observational data for defining consecutive drought-to-flood transition events.

Study Configuration

• Spatial Scale: Eight catchments (case studies).
• Temporal Scale: Historical record, considering various time windows for event detection.

Methodology and Data

• Models used: Not applicable; the study assesses "event selection methods" and "threshold level methods" for event detection rather than hydrological models.
• Data sources: Observational streamflow time series data.

Main Results

• Different threshold level methods substantially alter the characteristics (number and timing) of selected drought-to-flood transition events.
• The impact of methodological choices is more pronounced in highly seasonal hydrological regimes compared to those with weaker seasonality.
• The time period used to define the maximum interval between drought and flood significantly influences whether transitions are detected.
• The probability of a transition occurring within a set time window can vary substantially depending on the methodology and the specific catchment.
• Previously applied methodologies are likely to fail in detecting broadly impactful historical transition events; for eight media-reported case studies, only three transitions were successfully detected.
• A qualitative assessment of streamflow time series revealed several potential pitfalls in the event detection process.

Contributions

• Provides the first clear assessment and definition of methods used to define consecutive drought-to-flood transition events.
• Highlights the significant impact of methodological choices (threshold levels, time windows) on event detection and characterization.
• Demonstrates the limitations of existing methodologies in detecting historically impactful drought-to-flood transitions.
• Offers recommendations for methodological choices and outlines priorities for future methodological development and research in this field.

Funding

Information not provided in the given paper text.

Citation

@article{Anderson2025What,
  author = {Anderson, Bailey J. and Muñoz‐Castro, Eduardo and Tallaksen, Lena M. and Matanó, Alessia and Götte, Jonas and Armitage, Rachael and Magee, Eugene and Brunner, Manuela},
  title = {What is a drought-to-flood transition? Pitfalls and recommendations for defining consecutive hydrological extreme events},
  journal = {Repository for Publications and Research Data (ETH Zurich)},
  year = {2025},
  doi = {10.3929/ethz-c-000787656},
  url = {https://doi.org/10.3929/ethz-c-000787656}
}