Improved Modeling Approaches Towards the mm SLR

Abstract

Accuracy requirements for the International Terrestrial Reference Frame (ITRF) are becoming increasingly more stringent, especially with regards to its origin definition and its scale stability. Satellite Laser Ranging (SLR) contributes unique information on the origin, and along with VLBI, for its absolute scale. Advances in our understanding of the coupling between the sub-components of system Earth require that we revisit our current modeling used in the reduction of SLR data. Over the past few years, the inclusion (or not) in our models of high frequency effects of the temporal gravity signals due to mass redistribution in the terrestrial system, has been a topic of heated discussions at venues such the EGU, AGU and various workshops. With the recent release of numerous products from global circulation models and, satellite and terrestrial observations, we are now able to examine the effect of such improved modeling in the analysis of several years of SLR data. We present results from such analyses and compare them to our nominal results, based on the currently accepted ILRS standards. Depending on the outcome of these tests, we anticipate that in the near future, ILRS will formulate a proposal to IERS for modification of the analysis standards related to the products contributing to the establishment of the future ITRFxx.