Dr. Annemarie Schneider, Center for Sustainability and the Global Environment, University of Wisconsin-Madison. We have entered the Urban Era: cities now form the basis of the human experience for the majority of the Earth’s population. Numerous reports have emphasized that cities today must meet the needs of growing populations and expanding economies, while at the same time minimizing their environmental impacts. Expansion of built-up land is often the most direct environmental impact manifested by urban growth, with far-reaching regional and global implications for climate, hydrology, and biogeochemical cycles that often extend beyond municipal boundaries. In this talk, I will describe our recent efforts to develop a consistent methodology for mapping urban expansion across large areas using earth observation satellite imagery and census data. Presented at the 2014 University of Wisconsin-Madison Geospatial Summit.