- The world's beaches face a dire future: 50 percent of them could disappear by 2100 due to erosion caused by climate change.
- A new study by Northwestern University scientists proposes that applying a weak voltage to these ecosystems could encourage the production of “bonding” materials that could make coasts more resistant to erosion.
- The idea is inspired by the shell-building biology of clams and other mollusks, and the approach would be less invasive and less costly than currently proposed coastal protection methods.
As the world continues to warm, scientists, engineers and governments are considering more drastic measures to protect precious ecosystems around the world. Coral reproduction accelerates evolution To improve heat resistance, engineers Testing ways to brighten clouds To increase the Earth's solar reflectance, some scientists A buoyant “curtain” could keep out hot water This prevents them from reaching ice shelves and glaciers.
Now scientists shocking Ideas on how to protect coasts around the world from coastal erosion. As sea levels rise, wind patterns change, and storms intensify, places where land and sea meet are among the places where ecosystems are hit hardest. So much so, some estimates suggest that half of the world's coasts could disappear by 2100. To combat this relentless coastal wear and tear, scientists at Northwestern University theorize that applying a weak voltage to these ecosystems could strengthen coastlines for generations to come. The results of this study were published in the journal Nature. Communication Earth and the Environment.
Current ideas for protecting coastlines include building massive infrastructure or injecting materials underground, both of which are hugely disruptive (and expensive) to the surrounding environment. Lead study author Alessandro Lotta Loria of Northwestern Polytechnic University decided instead to harness materials provided by coastal habitats — specifically, ions and dissolved minerals.
“My aim was to develop an approach that could change the status quo in coastal protection, consolidating marine matrices without using actual cement,” Lotta Loria said in a press statement. “I have systematically and mechanistically proven that by subjecting marine soils to a mild electrical impulse, it is possible to transform the minerals naturally dissolved in seawater into a solid mineral binder, i.e. natural cement, which consolidates them.”
The idea actually comes from shelled animals, such as mollusks, which convert ions and dissolved minerals in the water into calcium carbonate, which they use to form their shells. Of course, the metabolic energy of the animal kick-starts the process, so to set off a similar reaction throughout an ecosystem, it only takes a weak current of just 2-3 volts to convert some material into calcium carbonate. Increase it to 4 volts, and you end up with magnesium hydroxide and hydromagnesite, both of which are common in stone. These substances provide a kind of glue that holds the sand particles together, making the coast more resistant to weathering.
Streaming electricity into a salty, watery environment sounds like bad news for other creatures living in the area, but Lotta Loria emphasizes that these low voltages are imperceptible to wildlife. Scientists have used similar techniques to stimulate coral growth without seeing any adverse effects on the surrounding animals. Oh, and another bonus? It's completely reversible.
“Minerals form by locally increasing the pH of seawater near the cathode interface,” Lotta Loria said in a press statement. “When the anode is replaced by a cathode, the pH drops locally, dissolving previously precipitated minerals.”
For now, this particular relaxation technique has only been demonstrated in the laboratory, so the next step is to test this electroshock therapy in a real coastal environment. Hopefully, with just a little electroshock therapy, people and animals will be able to enjoy their favorite beach spots for generations to come.
Darren lives in Portland, owns cats, and writes/edits about science fiction and how our world works. If you look hard enough, you can find his previous writing on Gizmodo and Paste.