For the permafrost modelling the ice content in the ground is one of the crucial parameters. The information about the ice content can potentially be obtained by measuring the subsidence during the ground thawing. The SAR interferometry is the useful instrument to detect vertical surface displacements. The planned project is in the frame of the Helmholtz (HGF) Alliance „Remote Sensing and Earth System Dynamics“ (http://www.dlr.de/hr/en/desktopdefault.aspx/tabid-8082) and links to the EU FP7 programme “Changing Permafrost in the Arctic and its Global Effects in the 21st Century (PAGE21)”. The study site is the central Lena River Delta. In cooperation with the German Space Agency (DLR), University of Oslo and the Vienna University of Technology the SAR interferometry will be experimentally applied based on the TerraSAR-X data. Two expeditions to the Lena Delta are planned in 2013 and one expedition in 2014. Ground-based multi range measurements will be performed. Three ultrasonic sensors and ten manual devices for the subsidence measurements will be installed during the spring expedition (April-May 2013) to validate the remote sensing data. Assimilation of InSAR data into a transient permafrost model is the key aim of the project.