A methodology to derive precise landslide displacement time series from continuous GPS observations in tectonically active and cold regions: a case study in Alaska

• DOI: 10.1007/s11069-015-1684-z
• Publication Date: 2015-03-11T12:44:12Z
• Authors: Guoquan Wang; Yan Bao; Yanet Cuddus; Xueyi Jia; John Serna; Qi Jing
• Keywords: 13. Climate action; 0211 other engineering and technologies; 02 engineering and technology

Over the past 15 years, Global Positioning System (GPS) technology has been frequently used as a tool to detect potential earth mass movements and to track creeping landslides. In this study, we investigated 4 years of continuous GPS data (September 2006–July 2010) recorded at a landslide site in Alaska. This GPS station (AC55) was installed on an un-identified creeping site by the Plate Boundary Observatory (PBO) project, which was funded by the US National Science Foundation. The landslide moves with a steady horizontal velocity of 5.5 cm/year toward NEE 15° and experiences a steady subsidence of 2.6 cm/year. There is a considerable correlation between annual snow loading and melting cycles and seasonal variations in the landslide displacements. The seasonal movements vary year to year with an average peak-to-trough amplitude of 1.5 and 1.0 cm in vertical and horizontal directions, respectively. This study addresses three challenging issues in applying GPS for landslide monitoring in tectonically active and cold regions. The three challenges include (1) detecting GPS-derived positions that could be contaminated by the snow and ice accumulated on GPS antennas during cold seasons, (2) establishing a stable local reference frame and assessing its accuracy, and (3) excluding local seasonal ground motions from GPS-derived landslide displacement time series. The methods introduced in this study will be useful for GPS landslide monitoring in other tectonically active and/or cold regions.