My research uses near-surface geophysical methods to better understand processes in the shallow subsurface. Analyzing surface Ground Penetrating Radar (GPR) reflection data and cross-hole GPR tomography and vertical profiling, my research focuses on providing highly detailed images of the subsurface. With time lapse-imaging, I can relate the differences between images to changes in fluid movement or soil moisture. By using a variety of methods, I can provide complementary information about the Earth's physical properties resulting in more reliable interpretations of the subsurface.My research also uses inverse methods to better understand the uncertainty and limitations of models. Many studies produce models that provide information about the subsurface. However, the estimated model parameters contain uncertainty. By analyzing the uncertainty, I can produce more reliable and meaningful subsurface models. Understanding the uncertainty in parameter estimates will enable geoscientists and environmental managers to make better, more cost-effective decisions based on the results of geophysical investigations.Near-surface geophysics is becoming a more important and widespread technique to solve difficult, two-, three-, and four-dimensional problems, such as the geological response to climate change and the flow of contaminants. My research addresses fundamental problems, which will not only benefit the geoscience community, but also society in general.