GPM IMERG: Global Half-Hourly Satellite Precipitation Estimates

Global precipitation data is provided at a high spatiotemporal resolution of 0.1 degrees (approximately 10 km) every 30 minutes. This dataset, Version 07B, is the unified multi-satellite retrieval algorithm for the Global Precipitation Measurement (GPM) mission, synthesizing estimates from passive microwave and infrared sensors. The algorithm employs advanced techniques including the Goddard Profiling Algorithm (GPROF2021), intercalibration, and a Morphing-Kalman Filter for time interpolation.

Use Cases

• Flood risk assessment and early warning based on high-frequency, gridded precipitation estimates.
• Climate model validation and calibration using a globally consistent, long-term satellite precipitation record.
• Hydrological modeling for water resource management leveraging the 0.1-degree spatial resolution.
• Research on extreme weather events using the half-hourly temporal resolution to track storm development.

Strengths

• Provides high-resolution global coverage at 0.1 degrees every 30 minutes, enabling detailed spatiotemporal analysis.
• Integrates data from multiple satellite sensors using a unified, peer-reviewed algorithm (IMERG), improving estimate reliability.
• Uses advanced calibration techniques, including adjustment to the GPCP Satellite-Gauge product, to correct known biases over oceans.
• Is available under a permissive CC-BY-4.0 license, facilitating open research and redistribution.

Limitations

• Key metadata such as dataset size, row count, temporal coverage, and last update date are not provided by any source, hindering usability assessment.
• The description of the algorithm is highly technical, which may present a barrier to entry for users without domain expertise in remote sensing.

Provenance

Source

U.S. GPM team, utilizing the GPM satellite constellation.

Collection Method

Synthesized from multiple satellite passive microwave and infrared sensors using the Integrated Multi-satellitE Retrievals for GPM (IMERG) algorithm.

Geography

Global