Manolo, age 10: “Will we still be able to live on the beaches in 30 years?”
Generally speaking, to put it simply, the answer is no! But in reality, it’s a complicated question that involves at least three issues.
Frédéric Bouchette, University of Montpellier
First of all, the retreat of the shoreline—the line separating the sea from the land—is a phenomenon that everyone has noticed. In 30 years, this retreat will be even more pronounced in many places.
In other places, beaches are getting wider every year, sometimes by several meters. In fact, the width of a beach depends in part on the movement of the shoreline, which changes in completely unpredictable ways over time!
Surprisingly enough, these changes in the coastline are one of the most complex issues in coastal research. People can therefore live near the beach for a long time when the coastline is stable. In highly dynamic areas, however, a house facing the beach can, within a few years, end up far from the water or even underwater.
On the other hand, it is often said that rising sea levels caused by global warming are reducing the size of beaches. In fact, beaches adapt by rebuilding themselves higher and higher, compensating for the rising water levels. However, they can only adapt in this way if there is a sufficient amount of sand in the area in question. Where sand is lacking, the beach shrinks all the more rapidly as the rise in water levels becomes more pronounced.
Furthermore, even though the beach reshapes itself in response to sea level changes, nothing prevents the water from flowing behind the beach into the inland wetlands, which cannot adapt in the same way as the beach system. This phenomenon is gradually turning certain coastal areas into islands, and living on an island is not easy for many reasons, such as access, water supply, or exposure to storms.
Ultimately, your question is likely as much about law, ethics, the environment, and economics as it is about the physical sciences. To what extent are we willing to develop technologies and invest resources to live by the water?
There is much debate on these issues among scientists proposing solutions, local governments concerned with preserving their territories, and the national government, which must provide the necessary framework. We will inevitably be living near beaches 30 years from now, but it is now that we must decide how.
Frédéric Bouchette, Professor, University of Montpellier
This article is republished from The Conversation under a Creative Commons license. Readthe original article.