Meet the sargassum belt, a 5,000-mile-long snake of seaweed circling Florida

People remove Sargassum in Playa del Carmen, Mexico, in April, 2022. Researchers expect this year will bring another massive bloom, choking local ecosystems and tourism economies. (Elizabeth Ruiz/AFP via Getty Images)

It stretches over 5,000 miles. It weighs over 10 million tons. And it's circling around the Gulf of Mexico and the mid-Atlantic, where the right combination of currents and wind could push it ashore.

If you haven't heard of the great Atlantic sargassum belt, or even if you have, chances are high that you'll see it pop into your news feed at least once this summer. After a decade of record-breaking blooms, 2023's sargassum mass is again shaping up to cause headaches (literally and figuratively) for beachside towns and tourists.