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One farmer's seaweed discovery could help slow methane emissions — and change the world

Harvesting seaweed and climate change
How harvesting seaweed could help in the battle against climate change 06:56

As the effects of climate change accelerate, the U.N. says the strongest lever we have to reduce global warming is to curb the emissions of the greenhouse gas: methane. But emissions continue to accelerate. 

There may, however, be a game-changing method to slow methane emissions. On Prince Edward Island in Canada, farmer Joe Dorgan's unlikely discovery has the potential to change the world. 

Dorgan, who founded North Atlantics Organics, which produces and distributes organic seaweed, stumbled upon what is nothing short of a climate miracle — the seeds of which were planted through five generations of family farming along the shores of Prince Edward Island. Back then, farmers harvested seaweed for feed and fertilizer. 

So while beachgoers may consider seaweed nuisance, Dorgan knew from experience it was teeming with potential, CBS News meteorologist and climate specialist Jeff Berardelli reported for "CBS Saturday Morning." He sent samples of it to Dalhousie University in Nova Scotia to test for organic certification. Through that, it was discovered that the high uptake of natural vitamins and minerals in seaweed drove up reproduction and milk production in cows. 

Dorgan knew instinctively that seaweed would be healthy for cows, but research revealed an unintended consequence: seaweed made cows less gassy.

Globally, methane is responsible for 30% of global warming. Of that, livestock, such as cattle, account for about one-third of all methane emissions. 

"They [researchers] found out that feeding seaweed to cattle would reduce greenhouse gases by as high as 40%," Dorgan said.

Digesting roughage requires extra digestion from cows and causes cows to burp more. Those burps emit methane, a heat-trapping greenhouse gas that's 80 times more potent than carbon dioxide. 

In a year, a cow emits as much greenhouse gas as a small car. Because animal numbers have skyrocketed to help feed a growing human population, livestock now accounts for 15% of global emissions. 

The increase motivated chief scientist at Futurefeed, Rob Kinley, who worked with Dorgan on his organic certification 15 years ago, to find a seaweed species with even more methane-reducing power. 

"We started testing seaweeds from coastal Australia, and it wasn't long before the Asparagopsis species showed up, and it showed up in a big way. So big that we didn't even believe what we were seeing," Kinley said. "It took multiple runs of testing this before we believed what we were seeing, which was we couldn't find methane anymore."

Kinley's research showed Asparagopsis, a common type of red seaweed, has the potential to virtually eliminate methane emissions from livestock. But there are some obstacles to overcome — it's not easy to harvest from the ocean, so scientists are experimenting with farming it.   

Kinely's team, along with others like Josh Goldman, project leader at Greener Grazing, are getting much closer to perfecting the techniques. 

"The way that it shifts the ruminant function in the cow also makes the animal more energy efficient," Goldman said. 

Goldman is encouraged by the seaweed's versatility. He said cultivation only takes about 90 days, allowing for multiple cycles per year, and it can be grown by aquaculture operations almost anywhere if the climate is suitable.  

Feeding the 1.5 billion cows in the world, however, is a big lift.

"There are a lot of mouths to feed. But the good news is we only need to feed those cows 0.2% of their daily ration," said Goldman. 

Still, there's the challenge of encouraging cow owners to use the seaweed supplement.   

For that, Goldman says there's an incentive: adding seaweed to a cow's diet means they consume less food. And, he says, dairy farmers and cattle ranchers will likely be able to cash in, selling carbon credits for the emissions they reduce.     

Eliminating almost all methane from almost all cow's on Earth "would have a tremendous impact, roughly equivalent to eliminating all the emissions from the U.S., or the equivalent of taking every car off the road globally," Goldman said. 

That's a long way off, but then again, Kinley's work has come a long way since his initial discovery 15 years ago.  

"This will be a much bigger story even 12 months, 18 months from now. ... I am optimistic," Kinely said. 

While there's lots of optimism for this seaweed product, critics say it hasn't yet been proven at scale. It's clear that methane reduction from seaweed is effective in the short-term, but there's some fear that its effects may diminish over time as the cow's digestive systems adapt. 

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