Coral reef islands across the world could naturally adapt to survive the impact of rising sea levels, according to new research.
The increased flooding caused by the changing global climate has been predicted to render such communities – where sandy or gravel islands sit on top of coral reef platforms – uninhabitable within decades.
However, an international study led by the University of Plymouth (UK) suggests that perceived fate is far from a foregone conclusion.
The research, published in Science Advances, for the first time uses numerical modelling of island morphology alongside physical model experiments to simulate how reef islands – which provide the only habitable land in atoll nations – can respond when sea levels rise.
The results show that islands composed of gravel material can evolve in the face of overtopping waves, with sediment from the beach face being transferred to the island’s surface.
This means the island’s crest is being raised as sea level rises, with scientists saying such natural adaptation may provide an alternative future that can potentially support near-term habitability, albeit with additional management challenges, possibly involving sediment nourishment, mobile infrastructure and flood-proof housing.
The research was led by Gerd Masselink, Professor of Coastal Geomorphology in Plymouth, working with colleagues at the University of Auckland (New Zealand) and Simon Fraser University (Canada).