Arctic sea surface height from a multi-altimeter combination

Pierre Prandi (CLS, France)


Jean-Christophe Poisson (vorteX-io, France); Yannice Faugère (CLS, France); Amandine Guillot (CNES, France)

Event: 2020 Ocean Surface Topography Science Team Meeting (virtual)

Session: Science II: Large Scale Ocean Circulation Variability and Change

Presentation type: Type Forum

We present a new estimate of Arctic sea level based on the optimal interpolation of three altimeter missions. Measurements from SARAL/AltiKa, CryoSat-2 and Sentinel-3A are blended together providing an unprecedented resolution for this type of products.
The final gridded fields cover all latitudes north of 50°N, on a 25 km EASE2 grid, with one grid every three days over two years.
We use the Adaptive retracker to process both open ocean and lead echoes on SARAL/AltiKa thus removing the need to estimate a bias between open ocean an ice covered areas. SARAL/AltiKa also provides the baseline for the cross-calibation of CryoSat-2 and Sentinel-3A.
When compared to independent data, the combined product exhibits a much better performance than mono-mission datasets.
This combined Arctic sea level dataset, along with three mono-mission datasets (75km grid, monthly resolution) is freely available from AVISO.

Pierre Prandi