Ecosystem-based adaptation (EbA) is a strategy for adapting to the adverse impacts of climate change by harnessing nature and the services it can provide. It uses biodiversity and ecosystem services to help people adapt to the adverse effects of climate change. In coastal areas, this involves managing mangroves, coral reefs, seagrass, dunes and wetlands to strengthen the ecosystem services they provide, building their resilience to climate impacts, as well as that of nearby communities. EbA is especially important in coastal regions, as nearly 2.5 billion people (about 40 per cent of the global population) live within 100 km of the coast (UNDESA 2019). Marine and coastal ecosystems also harbour an enormous variety of the world’s biodiversity, and they provide many valuable ecosystem services.