NOAA forecasts larger-than-average Gulf of Mexico 'dead zone' bereft of oxygen

June 14 (UPI) -- The National Oceanic and Atmospheric Administration has forecast a larger than average Gulf of Mexico "dead zone" this year of 5,847 square miles. That's about the size of Connecticut.

It's a hypoxic area of low oxygen and it can kill fish and other marine life. It appears every summer, but the average size over 37 years is 5,205 square miles, according to NOAA.

"Reducing the impact of hypoxic events and lessening the occurrence and intensity of future dead zones continues to be a NOAA priority," said National Ocean Service Assistant Administrator Nicole LeBoeuf in a statement. "These forecasts are designed to provide crucial data to scientists, coastal managers and communities, and are used as guideposts in the development of planning actions."

These zones form from excess nitrate and phosphorus discharged from the Mississippi-Atchafalaya River Basin. Those discharges stimulate overgrowth of algae.

When the algae die and decompose and sink to the bottom of the gulf, oxygen in the water is depleted. The "dead zones" cause fish and shrimp to vacate the area.

The Mississippi River and Gulf of Mexico Hypoxia Task Force has a long-term goal of cutting the dead zone down to 1,900 square miles by 2025.

The forecasts by NOAA help predict how the hypoxia zone is linked to fertilizer chemicals in the Mississippi-Atchafalaya watershed.

In 2023, the Gulf of Mexico "dead zone" was smaller than expected.

According to a NOAA-supported survey done by Louisiana State University and the Louisiana Universities Marine Consortium scientists, the dead zone was 3,058 square miles that year and was the seventh smallest since record-keeping on it started in 1985.

NOAA said in 2019 that the zone was expected to grow larger in coming years due to changing global weather patterns, heavier rains and worse flooding.