World's Largest Deep-Sea Reef Found Off US

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R​esearchers have uncovered the largest deep-sea coral reef habitat in the world, and it sits just off the coast of the southeastern U.S.

S​cientists first found coral mounds on the Blake Plateau in the 1960s, but they had no idea of their size until the recent completion of a years-long mapping project. The plateau is a vast expanse of the continental shelf about 100 miles offshore, stretching from the Carolinas to South Florida.

"Past studies have highlighted some coral in the region, particularly closer to the coast and in shallower waters, but until we had a complete map of the region, we didn’t know how extensive this habitat was, nor how many of these coral mounds were connected," Kasey Cantwell, operations chief for NOAA Ocean Exploration, said in a news releases.

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Coral mounds are deep sea, cold-water versions of coral reefs.

T​he mapping project, carried out in phases over more than a decade, covered an area of about 10,000 square miles. The research included 31 sonar mapping surveys and imagery from 23 submersible dives. The multi-agency effort included NOAA, the U.S. Geological Survey and university researchers.

"Approximately 75% of the global ocean is still unmapped in any kind of detail, but many organizations are working to change that," said Derek Sowers, mapping operations manager for the Ocean Exploration Trust and the study's lead author.

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T​he Blake Plateau coral maps were recently published in the journal Geomatics.

T​he largest area of the reef, dubbed "Million Mounds" by scientists, is comprised of a stony coral typically found at depths between 656 and 3,280 feet, where there is no sunlight and the average water temperature is just 39 degrees.

L​ess is known about these cold-water corals than their tropical counterparts, which are widely studied and shown in beautiful photographs and video.

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T​he researchers who worked on the mapping project hope to shed more light on deep, cold-water corals and ways to protect them.

"The study highlights how much more we have to discover and learn about our oceans," weather.com meteorologist Kait Parker said.

Weather.com reporter Jan Childs covers breaking news and features related to weather, space, climate change, the environment and everything in between.

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