SWOT Simulated Nadir SSH: ECCO LLC4320 Model Output

SWOT Simulated Level-2 Nadir SSH from MITgcm ECCO LLC4320 for Science Version 1 provides simulated sea surface height data formatted to match the future SWOT satellite's Level 2 altimetry product. The data are generated by the high-resolution ECCO LLC4320 global ocean data assimilation model, which operates on a Lat-Lon-Cap grid with a nominal 1/48-degree (~2 km) horizontal resolution. This simulation aids in the development and calibration of algorithms for the operational Surface Water and Ocean Topography (SWOT) mission.

Use Cases

• Algorithm development for SWOT Level 2 sea surface height retrieval based on the simulated nadir altimeter data format.
• Validation of ocean circulation models using a high-resolution, data-assimilated simulation of global sea surface height.
• Assessing the impact of model resolution on mesoscale ocean feature representation, given the ~2 km nominal grid cell size.
• Preparing user workflows and software for the operational SWOT mission by testing with a realistic simulated data stream.

Strengths

• Derived from the ECCO LLC4320 model, a high-resolution global ocean data assimilation system with a nominal ~2 km horizontal grid.
• Formatted specifically to match the planned SWOT Level 2 SSH product definition, providing a direct tool for mission preparation.
• Available on multiple authoritative platforms (NASA Earthdata and Data.gov), indicating its recognized utility for the science community.

Limitations

• Critical metadata is missing: specific column names, row counts, and file sizes are not provided in any source description.
• Conflicting 'last updated' timestamps exist (2012 vs. 2026), casting doubt on the dataset's maintenance and currentness.
• The license is ambiguously listed as 'other-license-specified' without a clear definition of terms.

Provenance

Source

POCLOUD organization, using the MITgcm ECCO LLC4320 global ocean simulation.

Collection Method

Data assimilation model output rendered into the SWOT L2 SSH Product Definition Document (PDD) format.

Freshness

2026-04-09 21:46:31.456167

Geography

Global ocean coverage.