Adaptive Coastal Planning under Climate Change Uncertainty

Due to climate change, low-lying coastal areas all over the world are increasingly threatened by flooding or even permanent inundation due to combinations of sea level rise, storm surges and other extremes, which demand urgent action.

Some coastal communities decide to live with the risk, whereas in most places, dedicated measures such as dikes, sea walls, and nature-based solutions (or combinations thereof) are installed to protect human and natural systems, including ecosystem services.

Where there are limits to adaptation, a managed retreat may be the only viable solution. We have to respond by making changes to our infrastructure in order to reduce this problem. We know the sea level will rise over the coming centuries, however it is not possible to predict when how much sea-level rise will happen where. Therefore we will have to make choices that are not perfect as we do not have all the information now.

In this study PhD study we develop future ‘adaptation actions’ to respond to this problem, and we evaluate how different choices might result in different benefits and drawbacks over time, depending on the future we will live in. Combinations of future actions are called adaptation pathways, which will help decisionmakers see potential future problems with regards to sea-level rise and inform planning responses for municipalities.

Gathering specialists applying the Dynamic Adaptive Policy Pathways methodology

Recently in collaboration with DTU NIRAS hosted a symposium with experts, policymakers, and practitioners to reflect on key lessons from applying the Dynamic Adaptive Policy Pathways (DAPP) methodology to sea-level rise adaptation in Denmark.

We explored the following main topics:

• Scalability – Aligning local, regional, and national adaptation efforts.

• Cross-Integration – Bridging climate adaptation across sectors and hazards.

• Transferability – Consistency in DAPP implementation across municipalities.

• Governance – Balancing long-term planning with short-term decision-making.

• Monitoring – Keeping DAPP as a continuous process.

Over the following months we will turn the lessons learned into a scientific manuscript comparing the lessons learned into an international context, and a technical note to help decision and policymakers make better decisions under climate change uncertainty.

This will lead to an increased need for the development of adaptation plans on a global scale but also within Denmark over the coming years. The project will result in an improved framework from lessons learned within the area of long-term climate adaptation planning in coastal environments from a multi-hazard perspective.

Gathering inspiration from abroad

During the PhD project there have been several opportunities to go abroad and get inspired / share knowledge with other students, professionals and colleagues. It was great to attend several conferences such as the Nordic conference On Climate Change Adaptation (NOCCA) and the International Conference on Coastal Engineering (ICCE)  in order and present the work we are doing, and be exposed to other ongoing research. There is a table below with the PhD milestones and highlights from courses and conferences.

During the Nordic conference on climate adaptation (NOCCA 2023), I was invited to give a presentation and workshop on adaptation pathways. It was a great opportunity to share the lessons learned from applying the DAPP method in New Zealand and Denmark. In particular, the workshop provided the opportunity to engage with the participants in a real-world case in Iceland, and explore potential future pathways. The outcomes have been included in the policy The Policy brief can be found here.

Some of the outcomes from the policy brief:

• Communities are key to build consensus around adaptation responses

• Communities are well-placed to identify vulnerabilities and thresholds of climate hazards

• Adaptive long-term thinking is the foundation for building a long-lasting plan