Analyses of altimetry errors using Argo and GRACE data
Event: 2015 Ocean Surface Topography Science Team Meeting
Session: Science I: Mean sea level monitoring: how to reconcile altimetry, tide gauges, land motion and other in situ observations?
Presentation type: Type Poster
Contribution: PDF file
Argo profiling floats are spread out over almost the global open ocean since 2004. However, they measure temperature and salinity vertical profiles, providing only the steric contribution to the total sea level content measured by altimeters. The missing mass contribution is derived from the GRACE data set from 2003 onwards.
The comparison is performed with the first objective of detecting global and regional altimeter mean sea level drifts. A second goal is to assess the impact of new altimeter standards (orbit, geophysical corrections, ground processing) and of new version of altimeter merged products such as the 2014 AVISO reprocessing or the Sea Level CCI data set. We also focus our work on sensitivity analyses of the method of comparison to various parameters. In particular, we determine to which extent the altimeter quality assessment is affected by a different pre processing of altimeter data, a sub sampling of the Argo network and a change of the reference depth used to compute Argo dynamic heights.
Keywords: Altimetry errors, Argo, GRACE, Mean Sea Level