Separating Multi Time Scale Signals in GPS Time Series in Greenland

GPS displacement measurements reflect a combination of many different geophysical processes occurring in the earth system. Greenland is experiencing Glacial Isostatic Adjustment (GIA) from past melting, as well as velocity perturbations from recent rapid ice mass change. In our study, we separate the long period, essentially linear GIA signal from shorter term variations in the GPS time series. We use GRACE data to compare with GPS measurement for a better understanding of seasonal variation in the region. Environmental data are used to correct the GPS time series in order to better understand the effects of glacial dynamics near a given GPS station. Our results suggest displacements caused by local environmental changes can be a significant component of the overall GPS signal in this area.