A MARTÍNEZ, HOST:
Too much sarcasm can be annoying. Too much sargassum can cause headaches for local residents and wreck tourism economies. And by sargassum, I mean the smelly, brown algae. And record levels are starting to wash up on shores in Florida, Mexico and the Caribbean. So it makes sense to get rid of it, but that creates another challenge. What do you do with a massive pile of seaweed? NPR's Emily Olson has that story.
EMILY OLSON, BYLINE: It's pretty common to smell sargassum before you even see it.
ALYSON CREAN: Residents have, for years, complained about the smell 'cause when it washes ashore, it smells like sulfuric acid or something.
OLSON: It smells like rotten eggs, says Alyson Crean. She's a spokesperson for the city of Key West in Florida. The longest stretch of public beach in Key West is only about a half-mile long, so it's not hard to rake stinky piles of sargassum off the sand every morning. But it costs the city about a million dollars each year, she says. And that's a cost that could rise.
CREAN: Our Tourist Development Council is freaking out.
OLSON: Research shows that excessive sargassum levels may cause nausea and respiratory issues. And now scientists think it could contain some heavy metals like arsenic, and that makes leaving it all on the beach dangerous to local ecosystems. But taking it off the beach leaves you with giant piles of stinking seaweed. So researchers and private companies have tried turning it into fertilizer, biofuel or plastic. But it's not so easy.
PADDY ESTRIDGE: Because it's poisonous, you have to process it to make it usable to make things. And that can be too expensive for any large-scale use. I mean, there's millions and millions of tons of it.
OLSON: That's Paddy Estridge, CEO of Generation Seaweed. It's a U.K. startup that thinks it may have finally found a commercially viable solution.
ESTRIDGE: We are building an automated robot called the AlgaRay, which is designed to intercept and sink sargassum before it can reach the coast.
OLSON: This slow-moving robot could drag sargassum down to depths of about 200 meters. That pops the air pods that keep sargassum afloat, sending the seaweed to a watery grave. And more importantly, it traps all the carbon that it holds, which could be a scalable way to fight climate change.
ESTRIDGE: It's a bit like an ocean Roomba to try and clear up the seaweed blob.
OLSON: The AlgaRay is still in testing phases, but Estridge hopes it might be ready to work by next summer.
Emily Olson, NPR News.
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