Nikoo et al. (2025) Assessing the fidelity of multi-satellite precipitation estimates for drought monitoring in a mountain water tower to arid basin system

Identification

• Journal: Journal of Arid Environments
• Year: 2025
• Date: 2025-11-20
• Authors: Mohammad Reza Nikoo, Moein Tosan, Rouzbeh Nazari, Masoud Vahabzadeh, Maryam Karimi, Ehsan Zarrinabadi
• DOI: 10.1016/j.jaridenv.2025.105519

Research Groups

• Department of Civil and Architectural Engineering, Sultan Qaboos University, Muscat, Oman
• Department of Irrigation and Reclamation Engineering, University of Tehran, Iran
• Department of Civil Engineering, The University of Memphis, Memphis, TN, USA
• Department of Civil Engineering, Iran University of Science and Technology, Tehran, Iran
• School of Public Health, The University of Memphis, Memphis, TN, USA
• Department of Soil Science, University of Manitoba, Winnipeg, Canada

Short Summary

This study evaluates the fidelity of four multi-satellite precipitation products (SPPs) for drought monitoring in the topographically complex Isfahan region, Iran, finding IMERG-V07 to be the most dependable for accurately capturing precipitation patterns and drought events.

Objective

• To assess the comparative accuracy and fidelity of four leading multi-satellite precipitation products (IMERG-V07, PERSIANN-CDR, CHIRPS, and GSMaP-V8) for drought monitoring in a topographically complex mountain water tower to arid basin system (Isfahan, Iran).

Study Configuration

• Spatial Scale: Isfahan, Iran, characterized as a mountain water tower to arid basin system with sharp topographic gradients.
• Temporal Scale: Twenty years (2004–2023).

Methodology and Data

• Models used: Not applicable (SPPs are products being evaluated, not models used in the study's methodology).
• Data sources:
  • Satellite Precipitation Products (SPPs): IMERG-V07, PERSIANN-CDR, CHIRPS, and GSMaP-V8.
  • Ground validation data: Dense network of 85 rain gauges.
  • Drought monitoring index: Standardized Precipitation Index (SPI).

Main Results

• IMERG-V07 and CHIRPS demonstrated the best capture of local precipitation patterns.
• PERSIANN-CDR exhibited a significant wet bias, overestimating precipitation by more than 14 mm/month during major drought periods.
• GSMaP displayed a systematic dry bias across the study area.
• For drought monitoring using the Standardized Precipitation Index (SPI), IMERG-V07 was identified as the most dependable product.
• IMERG-V07 showed a high correlation with ground data (r ≈0.98 for SPI-6) and accurately identified drought events with minimal errors.

Contributions

• Provides a practical benchmark for the selection of Satellite Precipitation Products (SPPs) in similar topographically complex arid regions reliant on mountain water towers.
• Addresses a key knowledge gap regarding the comparative accuracy of SPPs across sharp topographic gradients from mountain water towers to arid basins.
• Underscores the critical importance of addressing product-specific biases in SPPs to prevent misrepresentation of hydrological risk and improve drought management strategies.

Funding

• Not explicitly stated in the provided text.

Citation

@article{Nikoo2025Assessing,
  author = {Nikoo, Mohammad Reza and Tosan, Moein and Nazari, Rouzbeh and Vahabzadeh, Masoud and Karimi, Maryam and Zarrinabadi, Ehsan},
  title = {Assessing the fidelity of multi-satellite precipitation estimates for drought monitoring in a mountain water tower to arid basin system},
  journal = {Journal of Arid Environments},
  year = {2025},
  doi = {10.1016/j.jaridenv.2025.105519},
  url = {https://doi.org/10.1016/j.jaridenv.2025.105519}
}