A generalized algorithm for vertical motion determination at global tide
gauges sites using satellite altimetry and tide gauge sea level measurements
Chung-yen Kuo1, C.K. Shum1 and Alexander Braun2
1
Ohio State University, USA
2
University of Calgary, Canada
The determination of vertical motion at tide gauge sites differencing observed sea
surface height changes measured by tide gauge and satellite altimetry is demonstrated feasible
by prior studies however, with large uncertainty (~several mm/yr or larger). Kuo et al. [2004]
demonstrated a novel technique applicable in semi-enclosed basin or large lakes combining
long-term (>30 years) tide gauge and decadal satellite altimetry (TOPEX/POSEISON) sea
level measurement in an adjustment formalism with the resulting vertical motion at tide gauge
sites <0.4 mm/yr. The demonstrated regions include the Great Lakes and Baltic Sea
bordering Fennoscandia. Here we describe a generalized algorithm, attempting not to be
limited by the assumption that the basin covering by tide gauges must have observed the same
sea level change, to provide an estimate of vertical motions at world tide gauge sites. This
algorithm potentially allows the study of non-enclosed ocean basins, as well as deformation
sources not only limited to glacial isostatic adjustment, including co-seismic and post-seismic
deformations. In particular, we describe results including the Alaskan tide gauge vertical
motions which exhibit non-linear vertical motion caused by co-seismic deformation.