Ocampo-Marulanda et al. (2026) Hourly-scale modeling of storm transitions in Southern Brazil with Markov Chains

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

Identification

• Journal: Natural hazards and earth system sciences
• Year: 2026
• Date: 2026-07-23
• Authors: Camilo Ocampo-Marulanda, Jefferson Vieira Santos, Julián David Mera-Franco, Álvaro J. Ávila-Díaz, Tiago A. E. Ferreira, David Henriques da Matta, Antônio Samuel Alves da Silva
• DOI: 10.5194/nhess-26-3489-2026

Research Groups

• Southern Brazil Flood Risk Group (SBFRG)
• Department of Atmospheric Sciences, University of São Paulo
• Brazilian National Institute for Space Research (INPE)

Short Summary

This study characterizes the temporal dynamics of storm intensity and persistence at the intraday scale in southern Brazil using a season-resolved Markov chain framework. The results provide actionable inputs for early warning, zoning, and climate risk management.

Objective

• Investigate the relationship between geomorphology and storm persistence at the intraday scale

Study Configuration

• Spatial Scale: Hourly precipitation data from 15 stations across southern Brazil's mountainous units, Southern Plateau, Southern Shield, Central Depression, and Coastal Plain.
• Temporal Scale: Intraday (hourly) resolution for a period of 18 years (2007-2024)

Methodology and Data

• Models used: Season-resolved Markov chain framework for storm state transitions
• Data sources: Hourly precipitation data from in situ stations

Main Results

• Peak mean intensities reach 9 to 11 mm h −1 in mountainous units, compared with maxima near 7 mm h −1 on the coast.
• Storms last roughly 11 to 13 h in the Southern Plateau and Southern Shield, and 15 to 17 h in the Central Depression and Coastal Plain.
• Transition probabilities indicate enhanced persistence of intense storms in orographic regions.

Contributions

• This study provides a novel approach for characterizing intraday storm dynamics and their relationship with geomorphology.
• The results offer actionable inputs for early warning systems, zoning regulations, and climate risk management strategies.

Funding

• Brazilian National Council for Scientific and Technological Development (CNPq) - Grant # 2019/25359-0
• São Paulo Research Foundation (FAPESP) - Grant # 2020/11747-7

Citation

@article{OcampoMarulanda2026Hourlyscale,
  author = {Ocampo-Marulanda, Camilo and Santos, Jefferson Vieira and Mera-Franco, Julián David and Ávila-Díaz, Álvaro J. and Ferreira, Tiago A. E. and Matta, David Henriques da and Silva, Antônio Samuel Alves da},
  title = {Hourly-scale modeling of storm transitions in Southern Brazil with Markov Chains},
  journal = {Natural hazards and earth system sciences},
  year = {2026},
  doi = {10.5194/nhess-26-3489-2026},
  url = {https://doi.org/10.5194/nhess-26-3489-2026}
}