Urban Systems As Place-Based Foci For Infrastructure Interactions

In considering the implications of climate change for interactions among various kinds of built infrastructure and environments, urban areas are often of special interest, for at least four reasons (SAP 4.6). First, urban areas are nodes where all of the kinds of infrastructures come together in a particular place and are integrated in support of the functions of the urban system; as we know from recent experience with major weather events in the US, this close dynamic interconnection increases potentials for cascading impacts from disruptions. Second, urban areas are where the demands for infrastructure services are concentrated: where infrastructure disruptions have the greatest impacts on comfort, convenience, mobility, and labor productivity for the largest number of people. Third, for reasons having to do with why they developed in those locations, many US urban areas are in areas especially vulnerable to impacts from climate-related extreme weather events, such as coastal areas or river valleys subject to flooding and severe storms. Fourth, urban areas are important more broadly for decision-making about climate change responses; they are where the votes are, the financial centers are, the media centers are, and often vicinities where both university and industrial centers of innovation are located. Urban areas matter profoundly in assessing cross-sectoral interactions among infrastructures (see the NCA Technical Input Report on U.S. Cities and Climate Change).