Floridians hoping to kick off summer with a relaxing beach day might want to check the shoreline first. A record-breaking bloom of seaweed is drifting toward the coast, and it could bring more than just a mess. The culprit is Sargassum, a brown floating algae that turns unpleasant fast once it hits land. And this year’s bloom is massive.
Scientists estimate the bloom spans over 5,500 miles and weighs around 31 million tons. That’s 40% larger than the previous record set in 2022, CNN reports. The seaweed has already begun appearing along parts of Florida’s Atlantic coast, too, and is expected to expand from there as the tide moves it toward the coastline.
Out at sea, Sargassum plays an important role. It floats on the surface and provides habitat for marine species like turtles, fish, and crabs. But when it washes ashore and begins to rot, it releases hydrogen sulfide gas.
The smell is often compared to rotten eggs and can be overwhelming in coastal areas. While the gas usually isn’t harmful in open air, it can cause problems in enclosed spaces.
Florida’s Department of Health warns that people with asthma or other respiratory issues may experience irritation. In some cases, jellyfish and other stinging creatures get trapped in the seaweed, too, creating another layer of risk.
Some believe the size of this year’s bloom may be tied to our ongoing climate change crisis. Warmer ocean temperatures and nitrogen pollution from fossil fuels and Sahara dust create ideal conditions for rapid algae growth.
Sargassum season usually peaks in June and July, but this year’s growth started as early as March. The NOAA is tracking the bloom using satellite data, and residents can report patches of seaweed on Florida beach areas through a dedicated form. If you do see any batches on your outings this year, you’ll want to avoid them as much as possible.