Every summer for the past eight years, huge algae blooms have taken over the beaches near Qingdao, a city in the Shandong province of China.
The bright green stuff has blanketed at least 13,500 square miles of ocean this summer, according to the South China Morning Post.
And this isn't the first time it's happened. In 2013, the blooms got as big as the state of Connecticut! Check out this year's algae infestation.
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The algae blooms every year on the beaches in Qingdao, on China's northeast coast between Beijing and Shanghai. The first blooms appeared in 2007 after seaweed farmers working south of Qingdao switched up how they clean off their rafts.
Farmers use the rafts to make nori, a type of edible seaweed that's popular in Japan. When the rafts are cleaned off in the spring, along comes the algae, which thrives off the leftover seaweed nutrients and the warm conditions in the Yellow Sea.
Researchers think the reason for the algae growth in Qingdao is that seaweed farmers started cleaning their rafts farther offshore. This gave the algae the chance to spread out and make its way to the shore up near the city.
See the rest of the story at Business Insider