Hurricane Barry reduces ‘dead zone’ in Gulf of Mexico

NEW ORLEANS — This year’s Gulf of Mexico “dead zone” is the eighth largest on record, but Hurricane Barry reduced its size from an expected near-record, the scientist who has measured it since 1985 said Thursday.

Every summer, a large underwater area with too little oxygen to sustain marine life forms off Louisiana as nitrogen and other nutrients from the Mississippi River Basin feed blooms of algae that die and decompose on the sea floor. That decomposition uses up oxygen from the bottom up.

A research cruise that ended early Wednesday measured it at 18,000 square kilometres, lead researcher Nancy Rabalais said during a media teleconference Thursday.

“It’s not as large as we expected,” but still stretched from the Mississippi River to west of Galveston, Texas, she said. Rabalais described the affected area as surprisingly large, given that Hurricane Barry’s waves had mixed oxygen back into the water.

“I would predict that in one week from now the area will be larger than it is right now, but we can only spend so much time on the water,” she said.

She said is is “still 2.8 times greater” than the goal of a U.S. federal-state task force created 19 years ago to try to reduce the area’s size.

Two task force members — Steve Thur, director of the National Oceanic and Atmospheric Administration’s National Centers for Coastal Ocean Science, and U.S. Department of Agriculture Undersecretary Bill Northey — also were on the conference call.

Hurricane Barry formed as a tropical storm in the Gulf on July 11 and made landfall two days later — 10 days before the measurement cruise began.