Miles O’Brien, PBS NewsHour science correspondent, investigates how a red seaweed called Asparagopsis taxiformis could dramatically cut methane emissions from livestock — one of climate change’s most overlooked contributors.
Key insights:
Livestock methane (primarily from burps, not flatulence) exceeds emissions from the entire oil and gas industry.
Adding just 0.5% seaweed to cattle feed reduced methane emissions by an average of 52%, with some cows reaching over 90% reduction.
The active compound bromoform disables the enzyme that converts stomach gases into methane, while also freeing up hydrogen as extra energy for the cow.
Australia has already approved the additive and sells low-methane burgers commercially, while the U.S. FDA approval process could take 5–10 years.