Observation of deformation in Central Asia with ERS and Envisat

Preliminary results from a combined InSAR-GPS study in the northern Tien Shan are presented. Constraints on vertical deformation derived from ERS and Envisat interferometry in the Northern Tien Shan are compared with motions measured by a dense GPS network. Particular emphasis is on the region surrounding Bishkek, Kyrzgystan however limited data, dramatic elevation changes, temporal decorrelation, and atmospheric effects make standard interferometry using an SRTM DEM challenging. We present constraints of tectonic deformation based on a least-squares method that attempts to extract temporal deformation from multiple interferograms using measurements from the GPS data to constrain the inversion.