Climate Change Risks Facing Urban Areas

technological advancement has led to a clearer understanding of future risks and impacts. With increasing urbanization, understanding the impacts of climate change upon the urban environment will become ever more important. Evidence is mounting that climate change presents unique challenges for urban areas and their growing populations. Where urban areas grow rapidly without regard to current and future resource demands and climate change, large numbers of people and their assets can find themselves vulnerable to a range of disruptive and damaging risks. These impacts extend far beyond the physical risks posed by climate change, such as sea-level rise and extreme weather events. Cities could face difficulties in providing even the most basic services to their inhabitants as a result of climate change. Climate change may affect water supply, ecosystem goods and services, energy provision, industry and services in cities around the world. It can disrupt local economies and strip populations of their assets and livelihoods, in some cases leading to mass migration. Such impacts are unlikely to be evenly spread among regions and cities, across sectors of the economy or among socioeconomic groups. Instead, impacts tend to reinforce existing inequalities; as a result, climate change can disrupt the social fabric of cities and exacerbate poverty. Although there is a burgeoning literature documenting climate change impacts in various cities, there are few comprehensive studies that evaluate the wider implications for cities across the globe. The purpose of this chapter is to identify and discuss the impact of climate change on cities, where an ‘impact’ is defined as a specific effect on natural or human systems, either positive or negative, that results from exposure to climate change.1 The first section describes the physical climate change risks faced by cities and the extent of their variation across cities. ‘Risk’ is defined here as the combination of the magnitude of the impact with the probability of its occurrence.2 The direct and indirect physical, economic, social and health impacts of these changes in cities are then reviewed in the context of existing vulnerabilities. Accordingly, impacts upon urban physical infrastructure, economies, public health and security are discussed, keeping in mind the differential impact of climate change upon specific vulnerable groups. The chapter then identifies key indicators of vulnerability to climate change for urban residents and cities themselves. Finally, the last section offers some conclusions and lessons for policy.