The primary aim of the project is to establish the current state-of the-art secular sea level rise from tide gauges.
To obtain reliable estimates from the global tide gauge network, corrections must be made for postglacial rebound and other vertical contaminating signals such as groundwater pumping and monument instability. Vertical corrections will be estimated by reprocessing a global GPS network including available sites located at tide gauges and a selection of stable IGS locations, to provide a reference frame.
However, GAMIT scientific GPS processing software does not yet include corrections for higher order ionospheric effects. So, my current activity is to work out and code these corrections for GAMIT.