Abstract's details

Homogeneous multi-mission 20 Hz sea level anomaly (20 Hz L2P) products available

Sabine Philipps (CLS, France)


Cécile Kocha (CLS, France); Alexandre Philip (CLS, France); Marine Lievin (CLS, France); Isabelino Denis (CNES, France); Carolina Nogueira Loddo (EUMETSAT, Germany)

Event: 2022 Ocean Surface Topography Science Team Meeting

Session: Application development for Operations

Presentation type: Type Poster

Contribution: PDF file


Since the launch of TOPEX/Poseidon and ERS-1 in the early 90’s more than 10 other Altimetry missions were launched and operated by different agencies. The level 2 data (destinated to expert users) are distributed using different file formats (binary, netcdf) and contain different geophysical standards used to compute the sea level anomaly. Some datasets evolve rapidly and are regularly reprocessed, whereas other datasets, especially from finished missions are seldom reprocessed or not at all (and therefore do not profit from new standards).

In the frame of the SALP (Service d’Altimétrie et de Localisation Précise) project supported by CNES (Centre National d’Etudes Spatiales) and of the Sentinel-3 Marine Altimetry L2P-L3 Service (operated under an EUMETSAT contract in the frame of the Copernicus Programme funded by the European Union) level 2P 1 Hz data are available to users for all the altimeter missions (TOPEX/Poseidon, Jason-1/2/3, ERS-1/2, Envisat, Saral/AltiKa, Sentinel-3A/B, GFO, Cryosat-2, HY-2A) in delayed time on AVISO+ ( https://www.aviso.altimetry.fr/en/data/products/sea-surface-height-products/global/along-track-sea-level-anomalies-l2p.html ), as well as in near-real-time and short-time-critical for Sentinel-3A, Sentinel-3B and soon Sentinel-6A.

Since 2021 level 2P 20 Hz data are also available on AVISO+ for Sentinel-3A, Sentinel-3B and Jason-3 for near-real-time and short-time-critical timeliness. Other missions (HY-2B and Sentinel-6A) will be added in 2022. Hereafter the value-added sea level anomaly L2P products are presented. They are easy to use (netcdf format) homogenous along-track mono-mission products, providing as much as possible the same updated corrections and models for the altimeter missions, in order to facilitate inter-mission comparisons. The products contain the sea level anomaly as well as all the corrections used to compute it. The sea level anomaly is provided with a validity flag, enabling users to discard data with spurious measurements. Furthermore an inter-mission bias is applied to have consistent time series since TOPEX/Poseidon.

The L2P 20 Hz products are the input products of the future L3 5Hz sea level DUACS products (see abstract MI. Pujol “Toward Higher resolution Level-3 altimeter products”).

The L2P 20 Hz service and its products will be presented in detail.

Poster show times:

Room Start Date End Date
Mezzanine Tue, Nov 01 2022,17:15 Tue, Nov 01 2022,18:15
Mezzanine Thu, Nov 03 2022,14:00 Thu, Nov 03 2022,15:45
Sabine Philipps