CAREER: Increasing the use of imaging geodesy for studies of tectonics, volcanoes, and glaciers

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For centuries, measurement of the shape of the Earth (called the science of geodesy) was necessarily time consuming. Even with new technologies like the Global Positioning System (GPS), vast portions of the Earth remain infrequently monitored for movement. Over the past 17 years, a new form of geodesy has rapidly developed whereby satellite images can be compared to infer movements of the Earth's surface. Called imaging geodesy, the synoptic aircraft or satellite views allow large regions to be surveyed densely without any human setting foot in the area. Imaging geodesy encompasses several different types of methods including Interferometric Synthetic Aperture Radar (InSAR) as well as the automated comparison of SAR and optical images via the techniques of pixel or feature tracking. These techniques have allowed vast areas of the Earth's surface to be monitored frequently for deformation for the first time and led to discoveries in a variety of fields (including signals caused by earthquakes, volcanoes, landslides, glaciers, groundwater, and human-induced ground deformation). Imaging geodesy has the potential to become as ubiquitous a tool as seismology, but there have been several limitations. The problem of data access is diminishing thanks to the NSF-funded GeoEarthscope archive and other data access initiatives. A key current limitation to the widespread use of imaging geodesy is access to easy-to-use, but flexible software to process the data and knowledge for interpreting the results. While there are commercial and open source packages for imaging geodesy, none of them is yet fully functional and well documented for all applications. We will undertake an integrated program of research and education, focused on making new observations of ground deformation with imaging geodesy and expanding the community of users through improved software and documentation including a textbook geared towards undergraduates and a set of lectures and activities aligned with the textbook content. These research questions have intrinsic scientific merit for understanding geophysical processes, as well as practical applications like finding geothermal resources, and the causes of sea level rise. We will use newly available InSAR datasets (especially from the GeoEarthscope archive) to address two research questions: 1) What is the nature and distribution of magmatic fluids beneath the U.S. and Mexican Basin & Range Province, and how are they related to surface tectonics? 2) Have glacier velocities in Alaska increased in the last 2 decades, resulting in thinning of the ice and deformation of the solid Earth?