SARAL Project: Near-Real-Time Sea Surface Height Anomalies from Satellite Altimetry

NASA SARAL Project data provides near-real-time (NRT) sea surface height anomalies (SSHA) from the AltiKa altimeter onboard the SARAL satellite. The dataset is a French-Indian collaborative mission launched on February 25, 2013, and includes improved orbit adjustments and altimeter corrections. More information on the mission is available from the AVISO website.

Use Cases

• Monitoring ocean currents and eddies based on near-real-time sea surface height anomalies.
• Assimilating data into operational ocean forecasting models based on the improved orbit accuracy.
• Studying sea level variability and trends based on the Ka-band AltiKa altimeter measurements.
• Calibrating other satellite altimeter products based on inter-satellite crossover adjustments mentioned.

Strengths

• Provides near-real-time data within 7-9 hours of measurement.
• Orbit adjustments yield an altitude accuracy of 1.5 cm (RMS), leveraging a 1 cm (radial RMS) accuracy GPS-based reference.
• Includes improved altimeter wind speeds and sea state bias corrections.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and total dataset size are unknown, which may limit suitability assessment.
• Last update date is unknown; freshness unverified.

Provenance

Source

Satellite with ARgos and ALtiKa (SARAL), a French (CNES) and Indian collaborative mission.

Collection Method

Satellite altimetry measurements from the Ka-band AltiKa instrument.

Time Range

Data collection began after the satellite launch on February 25, 2013; specific temporal coverage is not detailed.

Freshness

Near-real-time (within 7-9 hours).

Geography

Global ocean coverage from satellite observations.