Thanks to data collected by remote-controlled submarines, researchers from the University of East Anglia have confirmed the existence of a nearly oxygen-less "dead zone" the size of Florida in the Arabian Sea.
Called "Seagliders," the robots are roughly the size of a small person, but with a much greater diving capacity: They can spend months at a depth of 1,000 meters. Data from the two gliders deployed to the area shows that this "oxygen minimum zone" is one of the largest in the world, covering almost the entire 63,700-square-mile Gulf of Oman.
In an article recently published in Geophysical Research Letters, the researchers note that access to these waters had previously been limited by "piracy and geopolitical tensions."
Marine plants and animals rely on oxygen to survive and therefore can't live in a dead zone. These zones also have implications for climate change: Lack of oxygen alters the nitrogen cycle, producing the greenhouse gas nitrous oxide, which is 300 times more potent than carbon dioxide.
Dead zones are "a disaster waiting to happen," said Bastien Queste of the University of East Anglia's School of Environmental Sciences, who led the research, in a press release. Climate change has exacerbated the situation—warmer water holds less oxygen—and run-off from fertilizer and sewage has also contributed.
Queste's team is continuing to look into the causes of the Gulf of Oman dead zone's growth. The situation, Queste explained, is worse than researchers feared: The area is huge and only getting bigger. "The ocean is suffocating," he said.