The EU project KNOWING supports regions in Europe in their climate transformation. The focus is not only on reducing greenhouse gases, but also on adapting to specific climate risks. For the highly exposed coastal city of Naples, the SFINCS (Super-Fast INundation of CoastS) model plays a central role, particularly in assessing and reducing the risk of flooding in times of increasing extreme events.
SFINCS: Simulated reality as a decision-making aid
SFINCS enables the realistic modeling of flood risks resulting from combined effects, including storm surges, heavy rainfall, and sea level rise. It is a model that is particularly suitable for simulating individual extreme events over a few days. In addition to natural influences, it also takes into account urban infrastructure and planned adaptation measures – from dykes and green spaces to measures that improve the infiltration capacity of urban soils.
Impact of green infrastructure: a comparison of two scenarios
Figure 1: Flooding in Naples under different conditions. Depending on measures and conditions, flooded areas in Naples can be reduced by almost 24%. Credit: VU Amsterdam
An application scenario for Naples analyses how targeted urban adaptation measures can reduce the spread of flooding. Two strategies were modelled:
Scenario 1: Improved infiltration in selected urban areas based on the local climate action plan (SECAP) – with an average reduction in flood area of 1.42%.
Scenario 2: More comprehensive measure to improve urban infiltration in the entire city through the expansion of green infrastructure – with a significantly higher average reduction of 15.77%.
Both results are based on an extreme event with simultaneous heavy rainfall and storm surge components, projected for the years 2050 and 2100 under climate scenarios SSP2-4.5 and SSP5-8.5.
Climate policy: Up to 270-million-euro difference per flood
Figure 2: Cost assessment in euro in Naples. Depending on the extent of measures and climate conditions, costs per flooding scenario can rise to 463 million euro per event. Credit: VU Amsterdam
The models in KNOWING show that, depending on the measures taken by the city of Naples, the costs of flooding events can be reduced by several million euro per event. These are also part of a global climate policy that can mitigate the rise in the temperature curve and thus the progression of climate change. Ambitious climate policy in individual regions or denying it makes a difference. Residential buildings, educational institutions, and old oil tank storage and distribution sites are particularly affected by the flooding.
In Naples, failure to act on climate policy costs up to 270 million euro more per severe flooding event.
Nature-based solutions as added value
Figure 3: Posidonia meadows provide coastal protection by protecting beaches from erosion and reducing water movement. They filter the water, keep it clear, and serve as a habitat for many sea creatures. Posidonia is also important for oxygen production and carbon dioxide sequestration. Credit: Benjamin L. Jones on Unsplash
In addition, the municipality of Naples plans nature-based solutions in coastal areas, such as the restoration of Posidonia meadows (seagrass) and wetlands, which can lessen the impact of storm surges. Such measures strengthen ecological diversity and carbon sequestration and contribute to physical coastal protection, for example, by reducing current velocity and wave energy.
Model network creates a system understanding
The findings from SFINCS are part of an integrated modelling approach in the KNOWING project. The land use and infrastructure adaptations simulated there flow directly into other models, such as PALM-4U, which evaluates urban climate changes, or HWLEM, which enables conclusions to be drawn about future energy requirements in the event of heat stress.
Finally, all the results are brought together in the KNOWING System Dynamics Model. This model depicts complex interactions between climate change, social developments, political measures and technical interventions and makes it possible to develop robust climate paths for regions such as Naples.
In this way, SFINCS not only contributes to local risk assessment but also acts as an important piece of the puzzle in KNOWING’s larger goal: to design climate-resilient, sustainable transformation in a well-founded and networked manner.
About KNOWING
KNOWING is a Horizon Europe project that develops tools, models and participatory formats to support climate-transformation. By combining scientific analysis with local knowledge and stakeholder input, the project supports regions and sectors to understand climate risks, assess options, and design effective, inclusive pathways for change.