SARAL-AltiKa: Ka-Band Satellite Altimeter Data for Ocean Topography

SARAL-AltiKa is a collaborative satellite mission between the French space agency CNES and the Indian space agency ISRO. Its primary instrument, AltiKa, is an innovative Ka-band altimeter system dedicated to accurate measurement of ocean surface topography. The satellite flew on the same orbit as ESA's EnviSat until at least July 2016 to ensure continuity of long-term altimetry observations.

Use Cases

• Measuring ocean surface topography and sea level change based on the Ka-band altimeter data.
• Supporting operational oceanography and forecasting systems like MERCATOR by providing continuous altimetry observations.
• Contributing to global ocean data assimilation experiments (GODAE) for climate and environmental studies.
• Calibrating other precise orbit determination instruments using the onboard Laser Retro-reflector Array (LRA).
• Acquiring and distributing environmental data for localization via the ARGOS-3 system payload.

Strengths

• Mission designed for continuity, flying on the same orbit as the major EnviSat mission.
• Features an innovative Ka-band altimeter system, a successor to the RA-2 instrument on EnviSat.
• Data processing is integrated into the established CNES ground segment (SALP) that also handles Jason-2/3 missions.

Limitations

• Row count, column definitions, and specific file formats are unknown, limiting suitability assessment.
• Last update date is unknown; freshness of the provided dataset snapshot is unverified.
• Column-level documentation is absent; field semantics must be inferred after download.

Provenance

Source

CNES (French space agency) and ISRO (Indian space agency) via the CEOS_EXTRA organization on NASA EarthData.

Collection Method

Satellite remote sensing from the SARAL platform, carrying the AltiKa altimeter-radiometer, DORIS, LRA, and ARGOS-3 instruments.

Time Range

Data collection ongoing; the satellite was on the EnviSat orbit until at least July 2016.

Geography

Global ocean coverage.