ITRF2014 Evaluation with ILRS Data and Products

Abstract:

The development and release of the new realization of the International Terrestrial Reference Frame—ITRF2014 requires elaborate testing to ensure the quality of the final product. The evaluation effort ensures that the ITRF is of the indicated quality by its error estimates and the combination has not compromised the contributing techniques’ input. The International Laser Ranging Service (ILRS) contributes unique information that only Satellite Laser Ranging—SLR is sensitive to: the definition of the origin, and in equal parts with VLBI, the scale of the model. The ILRS analysts adopted a revision of the internal standards and procedures in developing our contribution to ITRF2014 from our eight Analysis Centers. Anticipating the release of ITRF2014 we worked on designing and executing tests using data and products unique to ILRS. In addition to the data contributed to ITRF2014, ILRS has several other targets, in lower and higher orbits, the SLR tracking data of which are used as independent data for the evaluation process. Since SLR data are primarily sensitive to the origin and scale definition of the TRF model, these model attributes are the best to be validated using SLR data. LAGEOS and ETALON data collected outside the span of data used in ITRF2014 can also evaluate the quality of the estimated velocity vectors. The use of independent SLR data evaluates the model throughout the period that such data are available. SLR data from low altitude missions can validate the performance of the model from the late ‘70s all the way to present (using e.g. STARLETTE and LARES data). This presentation will give an overview of the new model’s evaluation using exclusively ILRS tracking data and other ILRS products.