Half the world’s beaches to disappear by 2100
A Nature Climate Change article released today reveals that half the world's sandy beaches could disappear by the end of the century – but that with the right steps towards climate mitigation this threat could be reduced by up to 40%.
Predicting the future of sandy beaches
A group of scientists from the European Commission’s Joint Research Centre, IHE Delft and Deltares, has today published the state-of-the-art global projections of how sandy beaches around the world could change over the course of the 21st century. Their findings emerge from combining 35 years of satellite observations with 82 years of climate and sea level changes as predicted by a range of global climate models.
Climate mitigation and adaptation challenges ahead
The study shows that without climate mitigation and adaptation almost half of the world’s sandy beaches are under threat of near extinction by the end of the century. In addition to the loss of valuable ecosystems, the associated socioeconomic implications would be severe, especially in tourism-dependent communities where sandy beaches are the main tourist attraction. Small Island nations are among these more vulnerable regions.
In most parts of the world, the projected shoreline dynamics are dominated by sea level rise, meaning that moderate greenhouse gas emission mitigation could prevent up to 40% of the projected shoreline retreat globally.
Different challenges for different countries
Discussing the significance of the findings, Rosh Ranasinghe, Professor of Climate change impacts and coastal risk at IHE Delft, highlights their importance at both global and national levels.
“This is the first time fully probabilistic (as opposed to deterministic) projections of future coastline change have been provided at global scale, and as such the utility of the projections are high for emerging risk-informed coastal management/planning frameworks.”
He added that in addition to the global outlook, the group’s findings also provide country-by-country analyses that indicate major coastal adaptation needs for different countries.
“By the end of this century several countries, including Congo, Suriname, Comoros, Benin, Pakistan, Guinea and El Salvador could face losing more than 80% of their sandy coastlines. In terms of total length of coastline, Australia emerges as the potentially most affected country with 12,324 km – 15,439 km of sandy coastline threatened by erosion.”
Arjen Luijendijk, researcher at Deltares and TU Delft, sees a positive message from the present analysis as well: “While SLR will drive shoreline retreat almost everywhere, many locations show ambient erosive trends related to human interventions, which could be avoided by more sustainable coastal zone management practices. Site-specific coastal planning can mitigate beach erosion, like we do in The Netherlands”.
“Assuming a continuation of the present Dutch nourishment policy and its effectiveness until 2100 will result in sufficiently wide beaches at the Holland coast, that can cope with the projected shoreline retreat due to future sea level rise of up to 1 m and extreme storms”.
You can read the full Nature Climate Change article here.
Taking action
The projections detailed in the Nature article are expected to contribute to Chapter 12 of the Working Group I contribution to the sixth assessment of the Intergovernmental Panel on Climate Change (IPCC AR6), which will be released in 2021.