The "dead zone" of the Gulf of Mexico is a region of water depleted in oxygen harmful to marine life.

The annual "dead zone" of the Gulf of Mexico – a region of oxygen-depleted water off the coast of Louisiana and Texas and damaging to marine life – will be the second largest recorded this summer, scientists said Monday .

According to researchers at Louisiana State University, this year's area is expected to cover an area of ​​8,717 square miles, about the size of New Hampshire. The average dead zone of the Gulf is approximately 5,309 square miles; the record is 8776 square miles set in 2017.

A dead zone lies at the bottom of an expanse of water when there is not enough oxygen in the water to support marine life. Also called hypoxia, it is caused by a runoff of nutrients, mainly by an excessive application of fertilizer on agricultural fields in the spring.

Nutrients, such as nitrogen, flow from the North American corn belt into streams before ending up in the Gulf. Heavy rains caused near-record floods along the Mississippi River throughout the spring.

Oxygen deficiency conditions in the most productive Gulf waters stress and even kill organisms, putting biological resources at risk, including fish, shrimps and crabs caught here.

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A separate forecast of Federal scientists from the National Oceanic and Atmospheric Administration also predicted a dead zone of an unusual size, of about 7,829 square miles, which corresponds to the size of Massachusetts. NOAA cited "historical and sustained river flows" as the cause of the large dead zone.


Nurdles, also known as "mermaid tears," are actually small plastic pellets used to make plastic items.

Last month, NOAA said discharges to the Mississippi and Atchafalaya rivers were about 67% above the long-term average.

According to NOAA, the dead zone of the Gulf of Mexico is one of the largest in the world.

"This year's area will be larger than usual because of floods, but the long-term trend is not changing," said Don Scavia, University of Michigan Aquatic Ecologist. in a statement. "Ultimately, we will never reach the 1,900 square kilometer reduction target of the Dead Zone until more serious steps are taken to reduce the loss of Midwestern fertilizer." in the Mississippi River system. "

Annual forecasts and measurements of the Gulf Dead Zone began in 1985. There is also an annual dead zone in Chesapeake Bay.

More: The "dead zone" of the Gulf of Mexico will persist for decades

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