The OECD is working to support governments to adapt to the risks from sea-level rise. The consequences of which are far reaching, with flood damage under high-end sea-level rise (1.3 metres) estimated to reach approximately 4% of world GDP annually. Marine ecosystems are similarly being severely impacted. The Special Report on Global Warming of 1.5°C estimates that coral reefs are likely to decline between 70% and 90% with a 1.5°C increase. If global warming reaches 2°C, more than 99% of coral reefs are projected to decline.
Infrastructure networks will be affected by the physical impacts of climate variability and change, such as increased coastal flooding. They will also play an essential role in building resilience to those impacts. New infrastructure assets should be prioritised, planned, designed, built and operated to account for the climate changes that may occur over their lifetimes. Existing infrastructure may need to be retrofitted, or managed differently, because of climate change.
In addition to making infrastructure resilient to change, additional infrastructure, such as sea walls, will need to be constructed to address the physical impacts of climate change. Coastal protection can reduce the future costs of sea-level rise by 2-3 orders of magnitude. However, in the context of rising risks, there is a need to move to a flexible, forward-looking approach to resilience. This includes integrating hard infrastructure with nature-based solutions (e.g. protection or restoration of coastal ecosystems), new technologies for accommodating flood risk (e.g. permeable pavement), and potential managed retreat in some areas.