Improving Altimetry’s Ocean De-aliasing Correction Using Daily GRACE Updates
Event: 2017 Ocean Surface Topography Science Team Meeting
Session: Quantifying Errors and Uncertainties in Altimetry data
Presentation type: Type Poster
To correct for aliasing problems caused by the ~10 day repeat pattern of T/P and Jason 1-3, a non-tidal de-aliasing model constructed of the inverted barometer (IB) response and the Mog2D ocean model is currently applied. However, Mog2D, like many global ocean models, is expected to have relatively high errors in some parts of the ocean. Previous research suggests that a GRACE-based daily series may be more accurate for periods in the 2-20 day range than an ocean model, especially at higher latitudes. A new “swath” update solution is being created to resolve GRACE data into a near-daily, high-spatial-resolution gravity time series with relatively low expected errors. We compare this to the current de-aliasing model, over the GRACE time period. The ultimate goal is to create a better de-aliasing product out of the combination of the two, with the current model dominating at the highest frequencies, but GRACE dominating at periods greater than two days.