Dear TRF User:
We are pleased to announce that JTRF2020, the NASA JPL contribution to ITRF2020, is ready to be released and distributed to the community. JTRF2020 has been computed with SREF (Square-root Reference frame Estimation Filter), JPL’s newly developed software for sequentially determining terrestrial reference frames based upon a square-root information filter and smoother algorithm.
JTRF2020 assimilates frame inputs from IGS, IVS, ILRS, and IDS making use of position observations from 525 GNSS, 194 DORIS, 116 SLR, and 96 VLBI (a total number of 931) stations and outputs smoothed daily positions and EOPS expressed at noon.
JTRF2020 main output consists of 16839 daily “gzipped” SINEX files in the ‘VARIANCE-COVARIANCE’ format containing station positions along with full normalized covariance information.
For those of you interested in JTRF2020, JTRF2020 daily SINEX files (containing solely station positions) can be accessed from the following URL:
For a description of the directory structure, the file naming conventions, and instructions for downloading the JTRF2020 files, we invite you to consult the README.md file that can be found attached to this e-mail as well as here:
As of this writing, the URL
is being populated with the entire set of JTRF2020 products. We’ll be sending out an official email to the community as soon as the JTRF2020 website gets fully populated.
We wish to acknowledge the crucial contributions provided by the Technique Services (IVS, ILRS, IGS, IDS) and their tremendous efforts put into the re-analyses of the space-geodetic databases.
We also would like to thank the ITRS Combination Centres at IGN and DGFI for their gracious support throughout the JTRF2020 analyses.
For any comment, question or specific request, please do feel free to contact us. We will be delighted to accommodate your requests and to help you integrate JTRF2020 into your reduction procedures.
We hope you will be able to enjoy JTRF2020 and we really look forward to having your feedback.
With Our Warmest Regards,
Claudio Abbondanza,
on behalf of the TRF Team at JPL-Caltech
Richard Gross
Claudio Abbondanza
Mike Chin
Mike Heflin
David Martin
Jay Parke