GPM IMERG: Global Half-Hourly Satellite Precipitation Estimates

Global precipitation estimates are provided at a 0.1° x 0.1° spatial resolution (approximately 10x10 km) every half hour. The data is produced by the Integrated Multi-satellitE Retrievals for GPM algorithm, which merges observations from a constellation of passive microwave and infrared satellites. It uses advanced techniques including the GPROF2021 and CORRA algorithms, with bias correction and a Morphing-Kalman Filter for interpolation.

Use Cases

• Monitoring flood risks based on high-frequency, global precipitation estimates.
• Validating and calibrating regional climate models using satellite-derived rain rates.
• Analyzing long-term precipitation trends for climate change studies using the unified multi-satellite record.
• Initializing numerical weather prediction models with near-real-time global precipitation fields.

Strengths

• Provides half-hourly temporal resolution, enabling analysis of short-duration storm events.
• Offers a unified, global precipitation product by merging data from a constellation of satellites.
• Uses Version 07B, which supersedes older versions and incorporates algorithm improvements like GPROF2021.

Limitations

• Key metadata such as specific time coverage, data volume, and last update date is missing from all provided sources.
• The dataset's accuracy is subject to the limitations of satellite retrieval and interpolation algorithms over complex terrain.
• Column names and a complete data dictionary are not provided, which may hinder detailed analysis.

Provenance

Source

GES DISC (Goddard Earth Sciences Data and Information Services Center), NASA.

Collection Method

Satellite remote sensing data from the GPM constellation, processed through the unified IMERG algorithm.

Geography

Global