NEW ORLEANS (AP) – Scientists say tropical weather stirred up the Gulf of Mexico, reducing this year’s low-oxygen dead zone off Louisiana’s coast to the third-smallest ever measured.
Nancy Rabalais began measuring the area where there’s too little oxygen to support marine life in 1985. She says this year’s covers about 2,116 square miles, but the five-year average remains much larger.
The dead zone starts at the bottom and grows upward every summer off Louisiana, reaching into Texas waters.
It’s created as calm weather lets fresh river water form a layer above the denser saltwater in the Gulf of Mexico.
Fertilizer feeds algae, which die and then decompose, use up oxygen leaving the zone unlivable marine life.