Small Coastal Cities Under Climate Pressure: Nature as Infrastructure and Lessons from Morondava, Avarua, Honiara, and Cairns

Despite being at the forefront of climate change’s effects, small coastal cities are still underrepresented in international studies on urban resilience and policy debates. The function of ecological systems as vital infrastructure for enhancing climate resilience in small coastal urban systems is examined in this chapter. The chapter examines how natural ecosystems like mangrove forests, coral reefs, wetlands, and estuarine systems serve as protective infrastructure against climate hazards like sea-level rise, tropical cyclones, storm surges, and coastal erosion through a comparative study of four cities: Morondava in Madagascar, Avarua in the Cook Islands, Honiara in the Solomon Islands, and Cairns in Australia. The four cities show a common reliance on neighbouring ecosystems for environmental stability and coastal protection, despite significant disparities in economic resources, urban development patterns, and governance capabilities. Three different adaptation routes are identified by the analysis: ecosystem stewardship through community-led conservation efforts, ecosystem dependency in resource-constrained cities, and hybrid infrastructure models that combine ecological protection with constructed urban systems. The results highlight the significance of long-term environmental management, community involvement, and governance ability in maintaining nature-based infrastructure. In the end, the chapter makes the case that coastal resilience in small urban systems necessitates a fundamental change in planning practices, acknowledging ecosystems as essential parts of urban infrastructure that can support sustainable and climate-resilient coastal development rather than as incidental environmental assets.