Ligawa et al. (2026) Evaluating Rainfall Timing and Volume of Gridded Precipitation Products

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

Identification

• Journal: Water
• Year: 2026
• Date: 2026-09-15
• Authors: Teofilo Ligawa, Ciira wa Maina
• DOI: 10.3390/w18182298

Research Groups

• University of Nairobi, Department of Meteorology
• International Livestock Research Institute (ILRI)
• Trans-African Hydro-Meteorological Observatory (TAHMO)

Short Summary

This study evaluates the accuracy of Gridded Precipitation Products (GPPs) in East Africa by accounting for the zero-inflated nature of precipitation data and differences in spatial support. The results reveal that temporal phase misalignments are localised, with varying performance among GPPs.

Objective

• To evaluate the accuracy of ERA5, IMERG, CHIRPS, and TAMSAT against the Trans-African Hydro-Meteorological Observatory (TAHMO) network across East Africa.

Study Configuration

• Spatial Scale: Continental scale, focusing on East Africa.
• Temporal Scale: Daily to diurnal time scales.

Methodology and Data

• Models used: ERA5, IMERG, CHIRPS, TAMSAT
• Data sources: Trans-African Hydro-Meteorological Observatory (TAHMO) network

Main Results

• Temporal phase misalignments are localised.
• At the diurnal scale, GPPs and TAHMO assign different regimes at 58.1% of the stations.
• IMERG exhibits superior phase alignment and event detection.
• CHIRPS and TAMSAT preserve precipitation volume more accurately.

Contributions

• This study provides a novel approach to evaluating GPPs by accounting for zero-inflation and spatial support differences, contributing to improved hydro-meteorological applications in East Africa.

Funding

• This research was funded by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) under project code CC-AF-2018-001.

Citation

@article{Ligawa2026Evaluating,
  author = {Ligawa, Teofilo and Maina, Ciira wa},
  title = {Evaluating Rainfall Timing and Volume of Gridded Precipitation Products},
  journal = {Water},
  year = {2026},
  doi = {10.3390/w18182298},
  url = {https://doi.org/10.3390/w18182298}
}