The 2014 JPL Realization of the ITRS: JTRF2014
Abstract:A Kalman filter and smoother, KALREF, is used to determine the JTRF2014, a combined terrestrial reference frame (TRF) obtained by analyzing the input SINEX files submitted by the IDS, IGS, ILRS, and IVS for the computation of ITRF2014. JTRF2014 is determined by combining on a weekly basis time series of station positions and Earth Orientation Parameters (EOPs) along with local ties at co-located sites.
In the JTRF2014 the temporal evolution of the station positions is formulated by accounting for linear and seasonal terms (annual and semi-annual periodic modes). The residual station position is modeled as a white noise process whose variance is characterized by analyzing station displacements induced by temporal changes of planetary fluid masses (atmosphere, oceans and continental surface water).
The JTRF2014 frame will be delivered as a time series of weekly SINEX files containing the filtered and smoothed station positions and EOPs observed from the early 80s through the end of 2014 and predictions of station positions afterwards. Datum specification (origin, scale and orientation) of the resulting frame will be discussed and comparisons with previous ITRS realizations will be provided.