Introduction and Rationale
This initiative aims to address the challenges outlined in GPEX Science Question Q1: determining the sources and magnitude of uncertainties in precipitation estimates in data-sparse regions. While numerous datasets exist, these in situ and hybrid precipitation datasets need to be compiled, documented, and linked under a unified, accessible repository. This resource will maximize the utilization of existing coverage and support research, data assimilation, and model evaluation.
Website Objectives
Data Compilation and Inventory
Providing a comprehensive list, detailed metadata, and direct links to all publicly available ground and satellite-borne precipitation data collected over Africa across several decades.
Research Integration
Including links to descriptive research papers and publications that document the methodologies, characteristics, and validation of the listed precipitation products.
Community Outreach
Sharing project progress, analysis codes, and open-source tools to enable broader participation in the analysis of African precipitation data, supporting advanced methods like AI-assisted downscaling.
Data Inventory
The following datasets are key to our synthesis and analysis:
| Name | Reference | Domain | Temporal Coverage | Gridded/Ungridded | Link |
|---|---|---|---|---|---|
| Global Historical Climatology Network hourly (GHCNh) | Historical | Global | Access Data | ||
| African Rainfall Climatology version 2 (ARC2) | Africa | 1983-Present | Satellite | Access Data | |
| EumetSat Rainfall Estimate for Africa (RFE) | Africa | 2001-Present | Satellite-Gauge | Access Data | |
| Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) | 50°S-50°N | 1981-Present | Satellite-Gauge | Access Data | |
| CPC Unified Gauge-Based Analysis of Global Daily Precipitation | Global | Gauge | Access Data | ||
| NOAA Precipitation Reconstruction (PRECIP) | Global | Reconstruction | Access Data | ||
| The African Monsoon Multidisciplinary Analysis (AMMA) | West Africa | 1950-Present | Gauge | Access Data | |
| University of East Anglia Climate Research Unit (CRU) | Global | Gridded | Access Data | ||
| TAMSAT | Tropical Applications of Meteorology using SATellite data | Africa | 1983-Present | Satellite-Gauge | Access Data |
| Famine Early Warning Systems Network (FEWS NET) | Global/Regional | Access Data | |||
| TAHMO | Africa (20k stations) | Real-time | Gauge | Access Data | |
| DACCIWA | West Africa | Field Campaign | Access Data | ||
| PERSIANN | Global | Satellite | |||
| IMERG | Global | 2000-Present | Satellite-Gauge | ||
| ISCCP Weather State Data | NOAA-NCEI and NASA-GISS | Global | Satellite | Access Data | |
| Tropical Rainfall Measuring Mission (TRMM) | Tropical | Satellite | |||
| Rainsat | |||||
| Global Precipitation Climatology Project (GPCP) | Global | Merged | Access Data | ||
| University of Delware (UDEL) | Global | Gridded | Access Data | ||
| CPC Merged Analysis Precipitation (CMAP) | Global | Merged | Access Data | ||
| Global Precipitation Climatology Centre (GPCC) | Global | Gauge | Access Data | ||
| CMORPH | Global | Satellite | |||
| HIGHWAY | Lake Victoria | Field Campaign | |||
| Rain over Africa | Amell et. al. 2025 | Africa | Gridded | Access Data | |
| SASSCAL | Southern Africa | Gauge | |||
| 3DPAWS | Global | Gauge | Access Data | ||
| REGEN | Contractor et al. 2020 | Global (land only) | daily; 1 x 1 degree | Gridded | Access Data |
| MSWEP | Beck et al. 2019 | Global | 3hr; 0.25 x 0.25 degree | Gridded | Access Data |
Advancement of GPEX Working Group Goals
This project contributes directly to the objectives of all four GPEX Working Groups (WGs):
WG2: Data Development
Facilitating systematic evaluation and uncertainty quantification by compiling existing in situ and hybrid precipitation datasets.
WG3: Modeling & Prediction
Providing the essential observational foundation required for multi-model databases and common evaluation metrics to diagnose and reduce precipitation biases.
WG4: Capacity Development
Making precipitation datasets available for resource-challenged scientists, particularly from the Global South, enhancing regional and local capacity building.
WG1: Field Campaigns
Helping characterize observation gaps and inform GPEX strategies, such as planning logistics for future field campaigns.