Gulf of Mexico’s oxygen-starved ‘dead zone’ approaches record size

Rows of farm land near Holly Bluff Miss. are covered with backwater flooding last month

Rows of farm land near Holly Bluff Miss. are covered with backwater flooding last month

University of MI scientists are predicting that the Gulf of Mexico will have a very large "dead zone" in 2019.

A dead zone is an area of low oxygen that can kill fish and marine life.

The low-oxygen, or hypoxic, space is at possibility of duvet about 7,800 sq. miles (20,200 sq. kilometers) - roughly the size of MA or Slovenia, NOAA stated. The record is 8,776 square miles.

The US National Oceanic and Atmospheric Administration released its forecast for the year's hypoxic zone on Monday.

The Gulf of Mexico's dead zone is primarily human-caused, a result of nutrient pollution, including nitrogen and phosphorus from urban environments and farms, traveling through the Mississippi River watershed and into the gulf.

"While this year's zone will be better than long-established on yarn of of the flooding, the long-time duration pattern is mild no longer changing", University of MI aquatic ecologist Don Scavia, professor emeritus at the College for Ambiance and Sustainability, stated in a news birth. The map illustrates how runoff from farms (green areas) and cities (red areas) drains into the MS, delivering nutrients into the Gulf of Mexico and fueling the annual hypoxic zone. That would likely cause the dead zone to expand farther west. The nutrients feed algae, which die and then decompose on the sea floor, using up oxygen.

Scientists said heavy rain this spring is likely part of the reason for the predicted size. It's created by runoff from over-application of fertilizer on agricultural fields that filter straight into the Mississippi River which empties into the Gulf.

Rabalais has been measuring the hypoxic zone since 1985.

While nutrient inputs to the Gulf of Mexico vary from year to year because of natural swings in precipitation and discharge, USGS also tracks longer-term gradual changes in nitrate and phosphorus loading into the Gulf of Mexico from the Mississippi River.

An oxygen-starved hypoxic zone, commonly called a dead zone and shown in red, forms each summer in the Gulf of Mexico.

The turbulent flow of river water, saturated with fertilizers and other nutrients, rushed to the Gulf.

Fish and shrimp and other "swimming" organisms can leave the area in search of a better habitat, but clams, oysters and slow-moving crustaceans (including crabs) aren't so lucky.

The area could spread over 8,700 square miles (22,500 square km), scientists at Louisiana State University said on Monday - about the size of the state of MA, and five times the average.

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