Accuracy assessment of ocean tide models around Antarctica

Abstract

Accurate ocean fide models for the circum-Antarctic seas are required to remove unwanted signals from floating ice elevation and space-borne, time-variable gravity measurements (e.g., GRACE). We present accuracy assessments for several global (CSR4, FES2004, FES99, GOT00.2, NAO.99b, TPXO6.2) and Antarctic (CADA00.10 and CATS02.01) ocean tide models using coastal and pelagic tide gauges, gravimetric data and GPS records of ice shelf surface elevation. The accuracies of CSR4 and NAO.99b are poor in the ice shelf regions. The optimum model for the entire circum-Antarctic seas is TPXO6.2, with a root-mean-square deviation of ∼5-7 cm, ∼40% lower than the next best model, FES2004. The main exception is the Filchner-Ronne Ice Shelf where CADA00.10 and CATS02.01 most accurately represent observations from two sites near the Rutford Ice Stream grounding line. Copyright 2005 by the American Geophysical Union.