Thursday, July 21, 2005

Key Largo, Fl. – On July 11, 2005, a nation-wide press release described an incident that demonstrates the awesome force that hurricanes have on the ocean floor. Hurricane Dennis skimmed west of the Florida Keys on July 9 after tearing through Cuba. A day later, divers discovered that the wreck of the USS Spiegel Grove, a 500-foot artificial reef in 130 feet of water off Key Largo had been tipped from its side to sit upright by the storm. Just miles from the wreck site, in half the water depth, sits the nation’s only undersea laboratory, Aquarius.

Owned by the National Oceanic and Atmospheric Administration’s (NOAA) Undersea Research Program and operated by the University of North Carolina Wilmington, Aquarius is a unique national asset – it is the only undersea research platform of its kind in the world. It rests 63 feet underwater and 3.5 miles offshore at Conch Reef in the Florida Keys. The 42-foot-long living chamber sits on a 120-ton baseplate anchored to the seafloor. Aquarius "aquanauts" live and work on the seafloor for extended periods using a special diving technique called saturation diving. For almost two decades, first off St. Croix in 1986 and for 12 of the last 13 years off Key Largo, Aquarius has survived numerous tropical storms. Craig Cooper, operations director, observed, “Each storm teaches us a new lesson and new respect for their power.”

In 1998, Hurricane George taught the Aquarius team one of those lessons when it broke one of the Aquarius baseplate legs. The Aquarius team then drove embedment anchors into the seabed and chained the habitat and baseplate down. Hurricane Dennis loosened the chains a bit and tore some fiberglass decking from a gear storage platform, but the habitat was otherwise unmoved and unharmed.

The power to do such damage comes from the strong currents associated with storms, but more importantly from the waves and surge created on the bottom — power strong enough to tip a 500-foot ship. As reported by NOAA’s National Data Buoy Center (http://www.ndbc.noaa.gov/station_page.php?station=42039), wave heights in the Gulf of Mexico exceeded 35 feet during the storm.

Whenever a storm threatens the Keys, coming within 1,500 miles of Conch Reef, saturation operations are halted. Aquanauts can be brought to the surface in 17 hours. The safety zone allows them to get out and fly home well before the storm.

A network of offshore ocean observatories is being developed and deployed that will monitor storms, providing real-time data on winds, waves, currents and much more. Several stations like this exist already in the Florida Keys as well as off North Carolina’s coast. NOAA’s Atlantic Oceanographic and Meteorological Lab in Miami helps sustain some of these stations and provide access to the data via Web site (http://www.coral.noaa.gov/seakeys/real_data.shtml). The lab will soon install a real-time data package at Conch Reef in partnership with Aquarius.

Building this new network will require many instruments on the seafloor. For every Spiegel Grove that is moved by currents, hundreds of buoys and instrument packages may be torn loose and lost. The data package at Aquarius will provide critical knowledge of how to sustain the network in an extreme environment.

During each Aquarius mission, anyone with Internet access can watch live Web cameras, read expedition journals from the aquanauts, view project summaries and pictures, and much more at the NURC/UNCW Aquarius Web site: www.uncw.edu/aquarius.

For more information, contact Otto Rutten, Associate Director or Craig Cooper, Operations Director, NURC/UNCW at 305/451-0233.