Description
Many cities are rapidly developing and expanding in conjunction with rural to urban migration and continuously growing urban populations. To allow for continuous growth over the long term, urban development must be sustainable. The focus of sustainable development varies greatly but is commonly broken down into three pillars: environmental protection, economic development, and equity and social justice. While the type of rapid development and urban expansion occurring in many cities demonstrates potential economic prosperity, such development may also exhibit diminishing environmental sustainability in part through the degradation of surrounding natural environments, as well as ignore concerns of inequity. The type of sustainable development needed to accompany rapidly growing urban populations is that which addresses human needs, contributes to well-being, and utilizes natural resources at a degree sustainable by the surrounding environment systems. Environmentally sustainable urban development (ESUD), such as urban green space, green roofs, and solar panels present the potential to achieve goals from each sustainability pillar. The goal of this study was to classify and map new (c. 2019) and existing (c. 2010) environmentally sustainable urban development (ESUD) through an object-based image analysis approach using NAIP aerial orthoimagery for six mid- to large-size cities in the United States. The specific objectives of this study are to: (1) identify ESUD and non-ESUD change for each study area, (2) estimate areal extents of ESUD change, and (3) compare ESUD change across study areas. The results indicate reliable mapping and areal estimation of urban green space and green roofs in urban areas. The reliability of mapping and estimating areal extents of solar panel change is inconclusive due to the relatively coarse spatial resolution of aerial orthoimagery utilized in this study. The three urban study areas in humid continental climate zones (Dfa) were estimated to have greater areal extent of existing urban green space, green roofs, and solar panels but less areal extent of new urban green space and green roofs when compared to the three study areas in humid subtropical climate zones (Cfa).
