Abstract：In order to evaluate the modeling accuracy of ocean tide load displacement in New Zealand, we use the observations collected from 189 GPS stations in New Zealand with the time span over eleven years. Then, the ocean tidal loading (OTL) displacements at 8 major (diurnal and semi-diurnal) tidal constituents are estimated based on the modified precise point positioning (PPP) algorithm in the static mode. We then carry out the inter-comparison of the OTL displacements between the GPS estimates and modeled values derived from seven global ocean tidal models and four earth models. The study shows that: 1) The results from GPS agree best with TPXO7.2 model; the RMS misfit of M2, N2, O1 and Q1 are within 0.5 mm and 0.7 mm in the horizontal and vertical directions, respectively. 2) Differences between different earth models exist mainly in M2 and N2 tidal constituents. 3) The residual vectors of OTL displacements estimated between GPS estimates and the model correction values at most sites present spatial consistency in both the amplitude and direction, and residual anomalies are observed at a few sites, which probably can be attributed to the deviation of the priori SNREI earth model.
