New code enables better and faster prediction of sea and coastal waves
Predicting how waves move towards the coast plays an important role in assessing coastal flooding, dune erosion and changes in the coastline. A new study by Deltares and IHE Delft, recently published in Copernicus' Geoscientific Model Development, presents an innovative solution for this: the SnapWave model.
The SnapWave model bridges the gap between offshore wave data and coastal conditions with remarkable speed and reliability.
Can be used along all open coasts
Wave buoys and global models typically provide data far from the coast. But by the time waves reach the coast, they have changed direction, become steeper and lost energy due to refraction and bottom friction. The simpler but lightning-fast SnapWave model accurately calculates this transformation, allowing coastal models to be calculated much more efficiently.
The researchers demonstrate that SnapWave, linked to global ERA5 wave data, provides accurate nearshore predictions in various case studies worldwide. The model is also open-source and can be used along all open coasts, particularly in data-poor regions.
Sometimes a few physical principles are enough to achieve your goal
Dano Roelvink, expert at Deltares
Linking to existing model systems
The development of SnapWave arose from a widely felt need for faster coastal models. Researchers at Deltares and IHE Delft searched for simple but effective algorithms on the margins of projects. These have been bundled into a code that can be directly linked to existing model systems such as Delft3D FM Suite, SFINCS and ShorelineS.
Coastal researchers around the world benefit directly from the newly developed method, as linked models calculate considerably faster. SnapWave is already being incorporated into other modelling environments, and Deltares and the University of Cantabria are working on a global application to predict coastal waves anywhere in the world
Researchers at Deltares and IHE Delft are currently also looking at modelling wave growth due to wind and the greatly accelerated simulation of long (‘infagravity’) waves, for example on coral coasts.
‘Sometimes a few physical principles are enough to achieve your goal,’ says Dano Roelvink, expert at Deltares. ‘We wanted to develop a model that calculates quickly, requires little data and still accurately predicts what waves do on the coast. Ultimately, this helps us to better assess coastal safety, especially in places where little measurement data is available.’
The full study, entitled “SnapWave: fast, implicit wave transformation from offshore to nearshore”, can be found here.
