1. Unified Analysis Workshop, 10-12 July 2017, Paris
The ILRS Products with ITRF2014/SLRF2014
V. Luceri, M.Pirri
e-GEOS S.p.A., ASI/CGS - Matera
E. Pavlis, M. Kuzmicz-Cieslak
GEST/UMBC – Baltimore, MD
G. Bianco
Agenzia Spaziale Italiana, CGS - Matera
Unified Analysis Workshop, July 2017, Paris

2. ITRF2014 implementation status
The ILRS ACs/CCs implemented the Post Seismic Deformation model in the SW for SLR data analysis, for combination and solution comparison/checking. 
After the release of the official ITRF2014, the ILRSA v61 was used to test the frame and compare with SLRF2008:
Analysis of SSC residuals
Analysis of Helmert parameters (Translations&Scale)
The official ILRS solution with ITRF2014 started in June 2017

3. Site Coordinate Residuals
wrms of SSC residuals – core sites
11.5 mm
5.3mm
11.4 mm
4.6mm

4. The updated ILRS daily product
The update include ITRF2014, mean pole and variable gravity field

5. SLR sensitivity to the TRF datum
0.5 mm
1 mm
1.5 mm
5 mm

6. ILRSA Translations: Tx
ITRF2014 Rate: (-0.00 ± 0.02) mm/yr Residual wrms= 3.63 mm
ITRF2008 Rate: (0.01 ± 0.02) mm/yr Residual wrms= 3.70 mm

7. ILRSA Translations: Ty
ITRF2014 Rate: (-0.06 ± 0.02) mm/yr Residual wrms= 3.24 mm
ITRF2008 Rate: (-0.14 ± 0.02) mm/yr Residual wrms= 3.41 mm

8. ILRSA Translations: Tz
ITRF2014 Rate: (0.12 ± 0.03) mm/yr Residual wrms= 6.27 mm
ITRF2008 Rate: (0.34 ± 0.03) mm/yr
Residual wrms= 6.53 mm

9. ILRSA Translations
ITRF DTRF JTRF2014

10. ILRSA Scale ITRF2014 Rate: (-0.09 ± 0.01) mm/yr Residual wrms= 2.39 mm

11. ILRSA Scale JTRF2014 Rate: (-0.01 ± 0.01) mm/yr Residual wrms= 1.25 mm
DTRF2014 Rate: (0.04 ± 0.01) mm/yr Residual wrms= 2.34 mm
ITRF2014 Rate: (-0.09 ± 0.01) mm/yr Residual wrms= 2.39 mm

12. Station Systematic Error Modeling
The ASC strategy was to limit application and estimation of biases to real events occurred and documented at the station
Engineering bias report from CDDIS database and from the stations through SLRMail
ILRS Data handling file adopted by the Anaysis Standing Committee listing:
bias to be applied
sites requiring bias estimation (to be kept at minimum)
unrecoverable data to be edited
Rapid, daily bias analysis report from the ILRS ACs
Bias time series estimated from a multi-year solution

13. ILRS Pilot Project on systematic errors
Weekly estimation of coordinates, EOP and range biases
Time frame:
Data: L1 and L2
A priori frame: ITRF2008
2 time series: unique and separate range biases
Available time series from 5 ACs
ILRSA combined series

14. Combined range biases Herstmonceux LAGEOS LAGEOS-2 Data handling file:
mm A 02:032: :042:00000 R

15. Impact on the site coordinates
3D coordinate residual WRMS

16. Impact on the scale Scale w.r.t. ITRF2008
Standard
L1-2 bias
Common bias
Standard wmean = mm
Bias est. wmean = mm
Same results if using ITRF2014

17. Path forward Points to note: ILRS ASC approach
Estimating the biases for all the sites together with the coordinates weakens the official products
The 7-day estimation is a medium/long term monitoring, not a quick QC
The medium/long term monitoring is essential to trace the range biases at centimeter level
ILRS ASC approach
make a table of biases using the time series of combined range biases from 1983 up to now
apply the bias values in the table for the official ILRS products
keep the table updated

18. Summary ITRF2014 tested and implemented in the ILRS processing chain
Scale issue investigated in the ILRS Analysis Standing Committee with a Pilot Project. The ILRS data handling file with the range bias table to be updated
Datum comparison made with DTRF2014 and JTRF2014: no apparent issue with the SLR scale