First Results of Project on Six-hourly EOP Piecewise Linear Offset Parameterization

Abstract

Continuous piecewise linear functions are a helpful way of parameterizing time series in least-squares adjustments employing a Gauss-Markov model. In this publication, we present the benefits for routine IVS Earth Orientation Parameter (EOP) estimation and show results of a project set up for demonstrating the feasibility of this approach. Before we start with that, we point out deficits of the current EOP estimation approach with 24-hour offsets and rates stemming from the mismatch of tabulated a priori EOP values at day boundaries and the two-calendar-day spanning of contemporary IVS observing sessions. In addition, the current EOP parameterization causes a mismatch of the IVS-derived EOPs labeled with “24 hours” with the daily EOPs derived from other space-geodetic techniques.