GEORGE P. WOOLLARD TECHNICAL LECTURE: APPLICATIONS OF SATELLITE GEODESY TO GLOBAL CHANGE RESEARCH

Satellite geodetic techniques such as GPS and InSAR have become increasingly accurate, more widely available, and more “user friendly” in the last two decades. As a result, they have found broad application in the Earth Sciences, including the study of plate motion, crustal deformation, earthquakes, volcanoes, and landslides. Increasingly, these tools are also being applied to a variety of local, regional and global change problems associated with anthropogenic activities, including subsidence of coastal deltas, changes and degradation of wetlands, surface deformation due to excessive water withdrawal from aquifers, sea level rise, rapid velocity changes of glaciers, and uplift of rock surfaces adjacent to glaciers and ice sheets associated with long term mass loss. Here I review some examples, including lowering of ground water tables in some urban areas of Mexico, associated with rapid population increase and increased development, and uplift in Greenland associated with multi-year ice loss, presumably related to global warming. In both cases, changes are both recent and rapid, and the availability of abundant, high quality satellite geodetic data has allowed time series analysis of the problem. Current challenges and longer term issues will also be discussed.