In what has become an annual occurrence, China's coastal city of Qingdao in July 2013 was inundated with the largest algal bloom in that country's history. Thick mats of algae lapped ashore, transforming sandy beaches into bright green lawns. The algae reportedly covered an area of 11,158 square miles, twice as much as the previous record.
Though local residents seemed to make the most of the spectacle, the swathe is likely a sign of an unbalanced ecosystem.
"Algal blooms often follow a massive discharge of phosphates or nitrates into the water. Whether it's farming, untreated sewage or some kind of industrial plant that is discharging waste into the water," researcher Dr. Brenda Parker said to the Guardian.