People Move, Populations Grow, and Cities Expand: Understanding Dynamics of Urban Expansion in 200 Capital Cities to Inform the 2030 Urban Development Agenda

Urban areas host now most of the human population worldwide, trends which will only exacerbate in the future. As the result of important socioeconomic transitions, large migrations of rural communities to cities are happening. Numerous advantages come from living in cities, such as access to jobs, health, and education. However, not all cities are growing sustainably, and this affects the living conditions of millions across the globe as access to safe drinking, sanitation, energy, and green space is not equitable distributed. The 2030 sustainable development agenda has as one of its goals to make cities and human settlements inclusive, safe, resilient and sustainable. To achieve this, countries are encouraged to enhance inclusive and sustainable urbanization, via planning and management. To track progress, countries need to monitor indicator 11.3.1: Ratio of land consumption rate to population growth rate. In this paper, we present the results of a spatio-temporal analysis of rates of urban expansion in 200 capital cities Worldwide. Using Trends.Earth SDG 11.3.1 and NASA's Landsat remote sensing data, we produced a consistent time series of urban extent at 30m resolution globally for the years 2000, 2005, 2010, and 2015, and were able to derive regional patterns of urban dynamics. Understanding how cities expand spatially under different environmental and socioeconomic contexts will allow us to understand the progress needed to achieve sustainable cities by 2030, and to significantly improve the living conditions of the most vulnerable populations.