| Date: | 2001-11-21 08:45:00 | |
| Sender: | Markus Rothacher <Markus Rothacher <Markus.Rothacher@bv.tu-muenchen.de>> | |
| Subject: | [SLR-Mail] No. 841: IERS Analysis Coordination | |
| Author: | Markus Rothacher | |
| Content: | ******************************************************************************** SLR Electronic Mail 2001-11-21 08:45:00 UTC Message No. 841 ******************************************************************************** Author: Markus Rothacher Subject: IERS Analysis Coordination Dear Colleagues, at the IERS Directing Board Meeting in Brussels in October I took over the responsibilities of the IERS Analysis Coordinator. This was made possible by the fact that two positions are now available at my institute for the tasks of the Analysis Coordinator and for the Combination Research Center activities. The two persons who are now working with me in this field are: Robert Dill (dill@bv.tum.de) Daniela Thaller (daniela.thaller@bv.tum.de) Robert Dill will mainly support the IERS AC work, whereas Daniela Thaller will mainly be working on CRC issues. The following actions have already been initialized or are planned for the next few months: A. Coordination of the CRC Activities ---------------------------------- (1) Mail Exploder and Web-Pages ---------------------------- An e-mail exploder has been set up by the IERS Central Bureau for the exchange of information between the CRCs and other interested groups and may be used by any person interested to share results, problems, ideas in the field of combination research within the IERS. The address is crc_forum@iers.org If you wish to receive the e-mails distributed by this exploder, please send an e-mail to Alexander Lothhammer at the IERS Central Bureau lothhammer@iers.org If you wish to distribute an e-mail of yours to this list, just send it to crc_forum@iers.org. A web page has been established for the IERS Analysis Coordinator activities at http://alpha.fesg.tu-muenchen.de/iers/ This web page will be maintained to reflect the goals and projects of the IERS Analysis Coordinator and the CRC activities. (2) SINEX-Format ------------ Starting with the IGS SINEX format description (Version 1.00) Daniela Thaller has put together a new version (Version 2.0) of the SINEX format including all the additions and modifications of the IVS and ILRS groups. The SINEX document together with a list of questions concerning the new version will be distributed to the Technique Coordinators of the IGS, IVS and ILRS for feedback and comments in the next few days. Interested groups may have a look at the format description available on the new web page mentioned above. With this step we hope to ensure that only one consistent format is followed by all the space techniques. As soon as the format definitions are finalized we will write a SINEX checker program that will be available for all groups to check their SINEX files in order to meet the format definition. We also intend to put together some guidelines on how SINEX files should be generated to make sure that a combination is possible without problems. Issues are e.g. how to handle constraints on the ERPs (UT1 for satellite techniques, continuity between ERPs of subsequent days, velocity constraints between collocated sites for ITRF submissions, etc.). (3) SINEX Data Pool ---------------- In order to test and develop their combination software packages the CRCs need to have access to a broad variety of SINEX files from different techniques. We therefore plan to establish a pool of SINEX files or links to SINEX file archives for the CRC activities. This pool will contain - all the contributions of the individual analysis centers to the ITRF2000 solution together with all the local tie information - SINEX files of the IGS and its combination centers - SINEX files from the ILRS and IVS pilot project to the extent available These SINEX files are thought to allow first tests and to modify the combination software packages to deal with the SINEX files produced by different techniques. (4) ”Weekly” SINEX Campaign ------------------------ It is also planned to come up with a time interval (according to the Technique Analysis Coordinators) for which the different techniques will deliver SINEX files for combination research, containing site coordinates and ERPs. The time interval covered by one SINEX file of the various techniques should be compatible (e.g. 1 week for GPS, 1 24-h session for VLBI and 1 or 2 weeks for SLR). These SINEX files will allow to - study the consistent combination of coordinates and ERP stemming from different techniques - detect and analyze systematic biases between the results of the different techniques - produce and compare time series of the different techniques - develop algorithms to allow the production of combined multi-year solutions with consistent site coordinates, site velocities and ERPs. - study weighting strategies and datum definition strategies These developments will be important steps in the direction of a rigorous combination of ITRF, ICRF and ERPs in the future. B. IERS Campaign to align EOPs to ICRF/ITRF2000 -------------------------------------------- This campaign was proposed by Jim Ray with the following objectives: - generate EOP series with the highest possible consistency with ICRF and ITRF2000 - achieve overall accuracy of 0.1 mas - understand the origin of systematic errors between EOP series of different ACs This campaign is thought to improve the consistency of the IERS products even before a rigorous combination of ITR/ICRF/EOPs becomes possible. The details of the campaign and the implementation plan are described on the new web pages of the IERS Analysis Coordinator. C. IERS Product Quality -------------------- The IERS AC will start to look into the quality of the present IERS products. This task will consist of: - putting together a complete list of the IERS products and their methods of generation, their availability, accuracy, etc. - assessing the status of the global network of fundamental stations - compile a list of the processing standards used by the analysis centers and the consistency with the IERS conventions - check the level of documentation of the IERS products and the guidelines about the use of the products Besides these topics the IERS AC plans a routine quality check of the IERS products. More details may be found on the web pages. We are looking forward to any feedback concerning the activities proposed here, the web pages, etc. With best regards, Markus Rothacher, Robert Dill, and Daniela Thaller The IERS Analysis Coordination Team -- -------------------------------------------------------------------------------- Prof. Dr. Markus Rothacher Phone : ++49-89-289-23191 Forschungseinrichtung Satellitengeodaesie Fax : ++49-89-289-23178 Technische Universitaet Muenchen E-mail: markus.rothacher@bv.tum.de Arcisstrasse 21 D-80290 Muenchen / Germany From: Markus Rothacher ******************************************************************************** |