Farokhzadeh et al. (2025) Drought Characteristics and Risks in Iran: A Four‐Dimensional Copula‐Based Approach Under Future Climate Scenario

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

Identification

• Journal: International Journal of Climatology
• Year: 2025
• Date: 2025-09-22
• Authors: Behnoush Farokhzadeh, Ommolbanin Bazrafshan, Maryam Mohamadi
• DOI: 10.1002/joc.70116

Research Groups

Not explicitly mentioned in the abstract.

Short Summary

This study investigated historical (1966–2019) and future (2020–2050) drought dynamics in Iran under the SSP2-4.5 scenario using SPI and copula models, revealing a general reduction in drought severity, duration, and magnitude but an increased likelihood of more frequent, less severe droughts and a moderate increase in severe drought probability for longer return periods.

Objective

• To investigate the dynamics of drought characteristics (severity, duration, magnitude, and peak intensity) in Iran under historical (1966–2019) and future (2020–2050) conditions using the SSP2‐4.5 scenario.

Study Configuration

• Spatial Scale: Iran, specifically 39 synoptic stations.
• Temporal Scale: Historical period (1966–2019) and future period (2020–2050).

Methodology and Data

• Models used:
  • Standardised Precipitation Index (SPI)
  • Copula-based multivariate models (T-copula identified as optimal)
  • HadGEM3‐GC31‐LL (Global Climate Model for projections)
  • LARS-WG (for downscaling climate projections)
• Data sources:
  • Data from 39 synoptic stations (observational precipitation data)
  • Downscaled climate projections from the HadGEM3‐GC31‐LL model under the SSP2‐4.5 scenario

Main Results

• A general reduction in drought severity, duration, and magnitude is projected under the SSP2-4.5 scenario.
• The T-copula was found to be the optimal fit for capturing dependencies among drought characteristics for 96% of stations in the future period, compared to 54% in the historical period.
• Conditional probabilities and risks for 20-year return periods showed an increase under SSP2-4.5, indicating a higher likelihood of less severe but more frequent drought events within shorter timeframes.
• For 50-year return periods, severe droughts remain rare but exhibit a moderate increase in probability and risk compared to the historical period.

Contributions

• Provides a comprehensive analysis of historical and future drought characteristics in Iran using both univariate (SPI) and advanced multivariate (copula-based) approaches.
• Quantifies the changes in drought severity, duration, magnitude, and peak intensity under the SSP2-4.5 climate change scenario.
• Demonstrates the effectiveness of copula models, particularly the T-copula, in capturing complex dependencies among drought characteristics under changing climatic conditions.
• Highlights the increasing likelihood of more frequent, less severe droughts and a moderate increase in severe drought probabilities for longer return periods, emphasizing the need for region-specific adaptation strategies.

Funding

Not explicitly mentioned in the abstract.

Citation

@article{Farokhzadeh2025Drought,
  author = {Farokhzadeh, Behnoush and Bazrafshan, Ommolbanin and Mohamadi, Maryam},
  title = {Drought Characteristics and Risks in Iran: A Four‐Dimensional Copula‐Based Approach Under Future Climate Scenario},
  journal = {International Journal of Climatology},
  year = {2025},
  doi = {10.1002/joc.70116},
  url = {https://doi.org/10.1002/joc.70116}
}