Assessment of Orbit Quality through the SSH calculation- Towards GDR-E standards

Annabelle OLLIVIER (CLS, France)


Sabine Philipps (CLS, France); Cécile Renaudie (CLS, France); Alexandre Couhert (CNES, France); Nicolas Picot (CNES, France)

Event: 2014 Ocean Surface Topography Science Team Meeting

Session: Precision Orbit Determination

Presentation type: Type Oral

The quality of the orbit ephemerides is crucial for the computation of the Sea Surface Height (SSH). Conversely, analyzing the impact of precise orbit ephemerides on SSH performances enables to describe their impact at different temporal scales and to detect remaining weakness in the orbit solution with a very fine precision.
Since GDR-D products release, many improvements in the POD solution were tested and GDR-E are getting prepared for a distribution planned as soon as the new international reference frame (ITRF2013) will be available, early 2015.
In the mean time, an interim orbit solution (preliminary GDR-E standards) was generated on CNES side, to be ingested in Jason-1 reprocessed data in 2014.

This presentation assesses two main subjects.
First, the quality assessment of this orbit is presented and the main posts of improvements considered in this series are declined. Notably, a more recent gravity field, new South Atlantic Anomaly management, more accurate solar radiation impact modeling are analysed...
Then, we will present the impact on SSH of the potential improvements that could be included in the future GDR-E products (new mean gravity field model EIGEN-GRGS.RL03.MEAN-FIELD, tuned geopotential terms, more reduced-dynamic approaches, new DTM-2013 atmospheric density model, atmospheric/hydrological loading modeling, ...).

In this study, mono-mission and multi-missions diagnosis are used. In particular, we focus on the effect of the different orbit solutions concerning long term trends and inter-annual signatures observed on the Sea Surface Height. Climatic scales stability is analyzed as well as regional and higher frequency signals.

Oral presentation show times:

RoomStart DateEnd Date
Ballroom Wed, Oct 29 2014,11:15 Wed, Oct 29 2014,11:30
Annabelle OLLIVIER