The Altimeter Sea Level Climate Data Record in the Copernicus Climate Service (C3S)

Jean-Francois Legeais (CLS, France)


Guillaume Taburet (CLS, France); Pierre Prandi (CLS, France); Antoine Delepoulle (CLS, France); Yannice Faugere (CLS, France); Isabelle Pujol (CLS, France)

Event: 2019 Ocean Surface Topography Science Team Meeting

Session: Regional and Global CAL/VAL for Assembling a Climate Data Record

Presentation type: Type Poster

Sea level is a key indicator of climate change and variability. Sea level integrates the ocean warming, mountain glaciers and ice sheets melting. Accurate monitoring of the sea level is required to better understand its variability and changes as well as the exchanges between ocean, land, cryosphere, and atmosphere. It is also fundamental for policymakers as it allows to better characterize the social and economic consequences of the sea level rise affecting coastal populations and all low-lying areas.
The satellite altimeter sea level has been measured by different successive missions since 1993. More than 70 cumulated years of measurements have now been reprocessed with the DUACS (Data Unification and Altimeter Combination System) production system.
In addition of the altimeter instrument, the sea level estimation strongly relies on other complex systems such as orbit solutions, reference fields and oceanic/atmospheric geophysical corrections. During the recent years, the ESA Sea Level Climate Change Initiative has been the opportunity to improve the homogeneity and stability of the altimeter sea level record.
Today, the altimeter sea level is used for two main kinds of applications: (i) The monitoring of the long-term evolution of the sea level for climate applications and the analysis of Ocean/Climate Index (such as the global and regional Mean Sea Level evolution). This requires a homogeneous and stable sea level record. Such dataset is produced within the Copernicus Climate Service (C3S). (ii) The retrieval of mesoscale signals in the context of ocean modeling and analysis of the ocean circulation at global or regional scale. This requires the most accurate sea level estimation at each time step with the best spatial sampling of the ocean. Such dataset is produced within the Copernicus Marine Service (CMEMS) (previously distributed by AVISO).
The main steps of the altimeter production system will be presented. Then, the characteristics and limits of the different products described above (C3S, CMEMS) will be presented in order to help the ocean and climate community on their optimal use for validation, assimilation activities as well as scientific studies.

Poster show times:

Room Start Date End Date
The Gallery Tue, Oct 22 2019,16:15 Tue, Oct 22 2019,18:00
The Gallery Thu, Oct 24 2019,14:00 Thu, Oct 24 2019,15:45
Jean-Francois Legeais