This year, NOAA predicts a massive "dead zone" the size of New Jersey will bloom in the Gulf of Mexico.
Motherboard's Brian Merchant reports on the cause and consequences of dead zones:
The phenomenon is caused by what the National Oceanic and Atmospheric Administration calls "excessive nutrient pollution"—a surplus of nitrate-heavy fertilizer runoff produced by agricultural operations along the Mississippi River. That runoff bleeds out from farms and ranches across the south into the nation's mightiest—and dirtiest—river, and eventually winds its way into the Gulf.
All those nutrients cause massive algae feeding-frenzies that suck up all of the available oxygen, creating what scientists call "hypoxic" (very low oxygen) and "anoxic" (no oxygen) zones. Dead zones. They occur in oceans all over the place, but the one in that consumes vast swaths of the Gulf of Mexico is especially huge. Here's how huge: this year, NOAA expects that dead zone will be between 7,286 and 8,561 miles wide.
Or, in the NOAA report's words, "That would range from an area the size of Connecticut, Rhode Island and the District of Columbia combined on the low end to the New Jersey on the upper end." That puts this year's aquatic death radius in the running to be the biggest ever—the largest Gulf dead zone on record thus far was the 8,481 square mile behemoth that grew in 2002.