Abstract's details
SWOT data validation on the Patagonian Continental Shelf: Optimized tidal and atmospheric corrections for submesoscale resolution
Event: 2025 SWOT Science Team Meeting
Session: Oceanography: Regional Validation
Presentation type: Poster
The Patagonian Continental Shelf presents unique challenges for SWOT altimetry validation due to complex tidal dynamics, intense atmospheric forcing, and distinctive bathymetric characteristics. This study advances beyond preliminary structure identification to establish rigorous validation protocols through comprehensive in situ measurements and optimized correction algorithms during SWOT's Cal/Val period.
We deployed a multi-platform observational network along KaRIn/nadir track #007, including: (1) bottom pressure recorder at San Matías Gulf (41°S), (2) deep-water lander at 52°S equipped with SBE37 and Aquadopp current/pressure profiler, (3) Puerto Deseado tide gauge (48°S), and (4) three offshore platform WaveRadars (53°S). Trajectories of three surface drifters that crossed the validation track during few days were also analyzed. This configuration enabled systematic evaluation of SWOT L3 products against high-quality reference measurements across diverse shelf environments.
Our analysis demonstrates that standard SWOT corrections significantly underperform in this complex, poorly-measured region. Through comprehensive intercomparison of tidal models (FES2022b, TPXO10v2, GOT5.5, EOT20, and regional barotropic solutions), we identified FES2022b as optimal for harmonic analysis. More critically, replacing SWOT's global Dynamic Atmospheric Correction (DAC) with a regional barotropic model and ERA5-based inverted barometer corrections yielded substantial improvements: correlation coefficients increased from values below 0.5 (at some stations below 0.2) to correlations above 0.8, even exceeding 0.9 for sea level anomaly values.
The optimized correction framework reveals hydrodynamic features undetectable under standard L3 product configuration, with enhanced variability resolution that demonstrates improved capability for detecting coastal submesoscale processes. Comparison with high-frequency regional model outputs further reveals temporal aliasing effects in SWOT measurements that could lead to misinterpretation of oceanographic phenomena; despite daily coverage during the Cal/Val period, the highly dynamic nature of continental shelf processes requires sub-daily sampling to fully capture rapid oceanographic variability. These enhanced capabilities achieve centimeter accuracy essential for resolving coastal submesoscale processes, establishing a robust methodological framework for SWOT validation in continental shelf regions with complex dynamics.
This approach provides critical insights for global Cal/Val efforts and operational oceanographic applications in tidally-complex environments.
Acknowledgments
This work was supported by Pampa Azul B6, SWOT-PATASWOT, and OSTST TOSTO projects. TOTAL Energies provided offshore observational data.
Back to the list of abstractWe deployed a multi-platform observational network along KaRIn/nadir track #007, including: (1) bottom pressure recorder at San Matías Gulf (41°S), (2) deep-water lander at 52°S equipped with SBE37 and Aquadopp current/pressure profiler, (3) Puerto Deseado tide gauge (48°S), and (4) three offshore platform WaveRadars (53°S). Trajectories of three surface drifters that crossed the validation track during few days were also analyzed. This configuration enabled systematic evaluation of SWOT L3 products against high-quality reference measurements across diverse shelf environments.
Our analysis demonstrates that standard SWOT corrections significantly underperform in this complex, poorly-measured region. Through comprehensive intercomparison of tidal models (FES2022b, TPXO10v2, GOT5.5, EOT20, and regional barotropic solutions), we identified FES2022b as optimal for harmonic analysis. More critically, replacing SWOT's global Dynamic Atmospheric Correction (DAC) with a regional barotropic model and ERA5-based inverted barometer corrections yielded substantial improvements: correlation coefficients increased from values below 0.5 (at some stations below 0.2) to correlations above 0.8, even exceeding 0.9 for sea level anomaly values.
The optimized correction framework reveals hydrodynamic features undetectable under standard L3 product configuration, with enhanced variability resolution that demonstrates improved capability for detecting coastal submesoscale processes. Comparison with high-frequency regional model outputs further reveals temporal aliasing effects in SWOT measurements that could lead to misinterpretation of oceanographic phenomena; despite daily coverage during the Cal/Val period, the highly dynamic nature of continental shelf processes requires sub-daily sampling to fully capture rapid oceanographic variability. These enhanced capabilities achieve centimeter accuracy essential for resolving coastal submesoscale processes, establishing a robust methodological framework for SWOT validation in continental shelf regions with complex dynamics.
This approach provides critical insights for global Cal/Val efforts and operational oceanographic applications in tidally-complex environments.
Acknowledgments
This work was supported by Pampa Azul B6, SWOT-PATASWOT, and OSTST TOSTO projects. TOTAL Energies provided offshore observational data.