CoAuthors

William Bertiger (Jet Propulsion Laboratory, United States); Bruce Haines (Jet Propulsion Laboratory, United States); Aurore Sibois (Jet Propulsion Laboratory, United States)

In this investigation, we used GPS-based precise orbit determination (POD) of the Jason-2 and Jason-3 satellites to evaluate and validate the performance of the Precise Orbit Ephemeris (POE) that is provided on the respective Geophysical Data Records. We investigated a variety of approaches for the GPS-based POD, including evaluating the impact of changes in the reference frame, the impact of GPS constellation orbit and clock products, the impact of data weighting and tracking data resolution, modernization of dynamic force models such as time-variable gravity and use of models of the effects of dynamic atmosphere and oceans. Our validation included internal metrics to evaluate orbit precision and data noise (i.e., post-fit residuals), and external metrics such as withheld satellite laser ranging tracking data to evaluate orbit accuracy and sea surface height crossover variance to evaluate relative performance. In this presentation, we extract just some of the results from these investigations that have already been presented at each of the Ocean Topography Science Team meetings from 2017-2020.