Studart et al. (2025) A Bivariate Return Period Copula Application of Flood Peaks and Volumes for Climate Adaptation in Semi-Arid Regions

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

Identification

• Journal: Water
• Year: 2025
• Date: 2025-10-15
• Authors: Ticiana Marinho de Carvalho Studart, João Dehon de Araújo Pontes Filho, Guilherme Ramalho Gomez, María Manuela Portela, Francisco de Assis de Souza Filho
• DOI: 10.3390/w17202963

Research Groups

Not explicitly stated, but likely institutions focused on hydrology and water resources in semi-arid regions, particularly in Brazil.

Short Summary

This study investigates the limitations of univariate flood frequency analysis in semi-arid regions by proposing a bivariate approach using copula functions to jointly model flood peak and a newly introduced "average flood intensity." It demonstrates that this bivariate method reveals significantly higher return periods for complex flood events, improving compound flood risk assessment and dam safety planning.

Objective

• To investigate the limitations of traditional univariate flood frequency analysis in capturing the full complexity of flood events in semi-arid regions.
• To improve compound flood risk assessment by applying a bivariate frequency analysis based on copula functions to jointly model flood peak and average flood intensity.

Study Configuration

• Spatial Scale: Jaguaribe River basin, Brazil, focusing on the Castanhão Reservoir.
• Temporal Scale: Analysis of the 2004 flood event (55 days for the main reservoir filling period); the methodology implies the use of historical flood data for frequency analysis.

Methodology and Data

• Models used: Copula functions for bivariate frequency analysis.
• Data sources: Historical flood records (discharge, reservoir capacity) for the Jaguaribe River basin, specifically for the 2004 event.

Main Results

• The 2004 flood event in the Jaguaribe River basin caused the Castanhão Reservoir to receive a discharge of more than 5 x 10^6 cubic meters (5 hm³) and fill from 4.5% to over 70% of its capacity in 55 days.
• A new variable, "average flood intensity," was proposed to better capture short-duration, high-volume floods until peak.
• For the 2004 event, the univariate return period of flood peak was 35 years.
• The joint return period, incorporating both peak flow and average flood intensity using bivariate frequency analysis, reached 995 years.
• This highlights a significant potential underestimation of flood hazard when relying solely on peak flow metrics in semi-arid regions.

Contributions

• Proposes and validates a new metric, "average flood intensity," to better characterize short-duration, high-volume flood events.
• Introduces a robust bivariate frequency analysis methodology using copula functions for compound flood risk assessment in intermittent river systems.
• Demonstrates that univariate flood frequency analysis can significantly underestimate the return period and hazard of complex flood events in semi-arid regions.
• Provides actionable information for climate adaptation, supporting adaptive rule curves and risk screening for dam safety planning in climatically variable regions.

Funding

Not mentioned in the provided text.

Citation

@article{Studart2025Bivariate,
  author = {Studart, Ticiana Marinho de Carvalho and Filho, João Dehon de Araújo Pontes and Gomez, Guilherme Ramalho and Portela, María Manuela and Filho, Francisco de Assis de Souza},
  title = {A Bivariate Return Period Copula Application of Flood Peaks and Volumes for Climate Adaptation in Semi-Arid Regions},
  journal = {Water},
  year = {2025},
  doi = {10.3390/w17202963},
  url = {https://doi.org/10.3390/w17202963}
}