GRRATS: Daily Satellite River Height Interpolations

GRRATS provides a continuous, 1km/daily time series of river water surface heights derived from multiple satellite radar altimeters. The dataset is processed to create a form more recognizable to the hydrological observation community. It serves as a preparatory resource for users to familiarize themselves with satellite data formats before the launch of the SWOT mission.

Use Cases

• Monitoring long-term river stage variations using interpolated daily height time series.
• Calibrating and validating hydrological models with satellite-derived water level data.
• Analyzing pre-SWOT satellite data formats and quality flags for user training.
• Studying continental-scale surface water storage changes from multi-mission altimeter records.

Strengths

• Integrates data from multiple established satellite missions (ERS-1, ERS-2, TOPEX/Poseidon, OSTM/Jason-2, Envisat).
• Provides processed, interpolated data at a consistent 1km/daily resolution for ease of use.
• Hosted by a major space agency (NASA), indicating a level of institutional curation.

Limitations

• Critical metadata is missing: specific column names, row counts, and exact temporal range are not provided.
• Conflicting 'last updated' dates exist between sources (2018 vs. 2026), creating uncertainty about data currency.
• The license is ambiguously listed as 'other-license-specified' without clear terms for reuse.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Heights derived from satellite radar altimeters (ERS-1, ERS-2, TOPEX/Poseidon, OSTM/Jason-2, Envisat) and interpolated.

Freshness

2026-04-09 23:08:42.007856 (from datagov, though this future date may be an error or placeholder; an alternative date is 2018-04-20)

Geography

Global