Contents
CNES_GRGS.RL05MF_combined_GRACE_SLR_DORIS
Presentation
CNES_GRGS.RL05MF_combined_GRACE_SLR_DORIS is complete to d/o 300. It contains:
- 1,135,000 time-variable coefficients
- 82,532 static coefficients (above degree 90)
A presentation of this mean gravity field is given here.
Data used
- DORIS+SLR mascons from January 1993 to March 2002
- GRACE+SLR RL05 monthly gravity field time series between April 2002 and October 2022
- GOCE-DIR5 for the static part between dg 91 and 300
The DORIS+SLR mascons solution uses:
- SLR data from Lageos1, Lageos2, Starlette, Stella, Ajisai and Lares satellites
- DORIS data from all DORIS-carrying satellites, from Topex to HY2A and Saral
- The mascons solution was converted to spherical harmonics between degree 1 and 40
Extrapolation
- The retrograde extrapolation of the trend coefficients (pre-1993) is obtained from a regression on the DORIS+SLR mascons
- The prograde extrapolation of the trend coefficients (post-2022) is obtained from a regression over the GRACE era (2002-2022)
There are two corrections to the slope of degree 2 before 1993:
- The slope of C20 (+0.2e-10 /year) is obtained from a SLR-based determination of C20 between 1980 and 1992
- The slope of C21/S21 (-6.82e-12 /year ; +1.40e-11 /year) is imposed to follow the conventional linear drift of the mean pole