The new time-variable gravity field model for POD of altimetric satellites based on GRACE+SLR RL04 from CNES/GRGS

Jean-Michel Lemoine (CNES, France)


Stéphane Bourgogne (Géode & Cie, France); Richard Biancale (CNES, France); Franck Reinquin (CNES, France)

Event: 2018 IDS Workshop

Session: SESSION III: Precise Orbit Determination

Presentation type: Type Oral

With the very long altimeter record that is presently available, the emphasis is now placed on the stability of the reference frame and on the control over a long time span of the geographically correlated errors.
This is why the accurate modeling of time-variable gravity and the geocenter is now a requirement of altimetry POD.
We present here the new time-variable gravity field model that has been computed from the fourth release of the CNES/GRGS GRACE+SLR time series of gravity solutions. It is based on GRACE and SLR data from August 2002 to August 2016. The inclusion of SLR data brings the ability to have a precise determination of the degree 2 as well as of the degree 1 (geocenter) of the gravity field. Outside of the GRACE era, the model provides the average annual and semi-annual variations of the gravity coefficients up to degree and order 90. For the sake of the long term stability of the orbits, the SLR-only time series from 1992 to 2002 is also provided for degrees 1 and 2.

Oral presentation show times:

Room Start Date End Date
Lagoa Do Fogo Tue, Sep 25 2018,14:00 Tue, Sep 25 2018,14:20
Jean-Michel Lemoine