January 23, 2006 — The ocean covers more than 70 percent of the Earth’s surface and much of it remains unexplored. Over the past few decades, technology has enabled humans to explore more of this underwater realm. Since NOAA’s mission is "to understand and predict changes in the Earth’s environment and conserve and manage coastal and marine resources to meet our nation’s economic, social and environmental needs," it is not surprising that NOAA undersea research and ocean exploration are often at the forefront in developing, modifying and operating advanced underwater technologies.

"The information gained from NOAA's underwater research and ocean exploration will help fill important ocean-based gaps in U.S. data that will be needed in a larger and more comprehensive Global Earth Observation System of Systems (GEOSS) being developed by more than 60 countries," said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. “Ultimately, the Earth observation system will help address emerging global issues and lay the groundwork for improved environmental decision-making and economic growth.”

Undersea Technologies
NOAA uses ships, underwater vehicles/submersibles, diving technologies and observation tools to transport — both literally and figuratively — scientific researchers, ocean explorers and other interested parties across ocean waters and into the depths to explore, examine, record and analyze the many mysteries of the deep.

SHIPS
Ships are a critical element in any oceangoing venture. Once a ship leaves the safety of its dock, however, it becomes a self-sustaining island — capable of transporting scientists, mariners and their equipment safety over the high seas.

The vessels used by NOAA are highly advanced mobile research platforms ranging in size from the 70 foot long research vessel (R/V) Cape Fear to the 274 foot long NOAA ship Ronald H. Brown. They provide stable platforms from which to deploy and retrieve divers, submersibles and numerous observation tools. They are equipped to collect a range of meteorological and oceanographic data from their onboard sensors. They also carry state-of-the-art electronics, computers and navigational/communications systems to analyze the data, and provide the crew with up-to-the-minute information about the ever-changing ocean environments.

Following a shipyard conversion, a former U.S. Navy ship will join the NOAA fleet as Okeanos Explorer, and when delivered in 2007, will be NOAA’s only vessel dedicated to ocean exploration and research. The ship will be capable of sending data, including images from the ocean floor to teams of scientists ashore by satellite and high-speed Internet pathways. Connections by standard Internet will make teachers, students and armchair explorers virtual members of the team of explorer-scientists. This ship-to-shore “telepresence” was tested successfully during the recent “Lost City” ocean expedition.

Undersea Vehicles
Undersea vehicles provide the means through which to explore the ocean’s abyssal depths firsthand. They allow humans to access the deepest reaches of the oceans so that scientists and explorers can make detailed observations of and collect samples from unexplored ecosystems. Because of these undersea technologies, remarkable new deep water ecosystems have been discovered — most notably hydrothermal vent communities that thrive in a high pressure environment devoid of light.

NOAA uses several different types of undersea vehicles:

• Human Occupied Submersibles:
  Through the use of human occupied submersibles, scientists can be physically transported to great depths of the oceans, far beyond the physiological restrictions of wet diving on the human body.
  Submersibles owned by NOAA include the Pisces IV and V, two of only nine submersibles in the world that can dive to depths of more than 6,562 feet. Both carry a pilot and two scientists. The submersibles are custom equipped to accommodate a variety of mission requirements. Standard gear includes external video and still cameras, two hydraulic manipulator arms, a conductivity/ temperature/depth profiler and sonar. Their use has provided unprecedented knowledge of the Pacific’s
  undersea volcanic processes and deep sea coral habitats. Through partnerships, NOAA can also lease other submarines, including the Johnson Sea Link, Delta and Alvin.
  
• Remotely Operated Vehicles: Remotely operated vehicles are unmanned underwater robots that are controlled by a pilot, via a tether that is spooled out from a support vessel (i.e., either a ship or another underwater vehicle). NOAA owns or leases ROVs such as the Kraken, Phantom, Hela, Jason/Medea and Spectrum II, which are fitted with camera, lighting and sampling systems that allow scientists to be virtually transported, through real-time video transmission, to depths beyond 21,385 feet. ROVs are commonly used in situations when scuba diving is not feasible due to depth and time limitations or when expensive manned submersibles are not cost effective. The advantages of ROVs include greatly extended bottom times, reduced human risk, reduced operating costs and the ability to deploy in harsher environments. ROVs have been used to conduct research in a wide range of environments — from the tropics to the poles.

  The NOAA Office of Ocean Exploration has ordered a deep-ocean ROV for use on the Okeanos Explorer. Built by Phoenix International, and a sister-vehicle to a new U.S. Navy ROV, this vehicle will dive up to a 19,685 foot depth and use high definition video cameras to provide exceptional new data from the ocean floor. The ROV will be part of a "two-body" system with a camera sled operating just above the ROV. This will provide additional sensors and lighting and a valuable overhead view for scientists. The system will also include an "X-bot," a very small ROV able to access confined or hazardous areas such as submarine caves.

• Autonomous Undersea Vehicles: Autonomous undersea vehicles are the most recent class of undersea research technology and can be described as a rapidly evolving class of untethered and unmanned submersibles. As the name suggests, AUVs can be preprogrammed to conduct various measurements, video surveillance, etc. Since they are independent of the surface, they are typically battery powered and controlled by computers using various levels of artificial intelligence. As platforms for scientific sensors, these vehicles operate at depths, over distances and with endurances that cannot be achieved with the same economies using human-guided devices. To date, most scientific AUVs have executed wide-area seafloor surveys and habitat characterization missions. NOAA operates a number of AUVs for these purposes and, through its Undersea Research Program, offers the use of two state-of-the-art vehicles to undersea researchers: a high-endurance Slocum-class underwater glider capable of diving to depths of 656 feet from Webb Research, and a new large-frame, deepwater Explorer-class vehicle capable of diving to 7217 feet from International Submarine Engineering. The latter vehicle will begin operations in the spring/summer of 2006.

DIVING

Scuba Diving
Scuba diving is an exciting way for scientists to study the underwater environment, and the most effective way to perform underwater experiments that require fine-scale measurements and a light touch. “Scuba” is the acronym for Self-Contained Underwater Breathing Apparatus, meaning that divers carry all the needed breathing equipment and gases with them, and is subject to the water temperature, pressure, currents and other environmental factors present at their diving depth. Scuba diving has many advantages over other modes of underwater exploration. Scuba divers have great freedom of movement under water because they swim with fins and without heavy equipment. Their gear is relatively inexpensive, simple to operate/maintain and requires a small support crew (or none at all). Despite all of these apparent advantages, recreational scuba also has its drawbacks. These include no direct link between the diver
and the surface, no method of communicating with the diver or monitoring his activities, and limited dive time and depth.

Advanced Diving
Advanced diving is a term used to describe all diving methods that exceed the limits imposed on depth and/or immersion times for recreational scuba diving. Advanced diving often involves the use of special gas mixtures (other than compressed air — nitrox and/or mixed gas diving for example) for breathing. While the recommended maximum depth for conventional scuba diving is 130 feet, technical divers may work in the range of 170 feet to 350 feet — sometimes even deeper. Advanced diving techniques include technical diving and rebreathers. Technical diving, like SCUBA, operates as an open-circuit system where the diver’s breath is exhaled into the water. The technical diver, however, carries several tanks containing the breathing gases needed for the dive and for the mandatory decompression stops.
Closed-circuit mixed-gas rebreathers recycle the diver’s exhaled breath, remove the carbon dioxide, and replace the consumed oxygen. This reduces the amount of gas that must be carried by the diver and increases dive time. Researchers like the increased mobility and absence of bubbles, but the technology is still complicated and expensive. The NOAA Diving Program and NURP collaborated to generate a safety standard, Minimum Manufacturing and Performance Requirements, for CCRs that will help increase the use of this technology. For more information on diving and decompression see the NOAA Dive Manual.

Saturation Diving
Even scientific divers that use advanced diving techniques are still limited by diving depth, gas mixtures and supply, weather and decompression obligations. Saturation diving, a technique developed by the U.S. Navy in the 1950s, allows scientists to stay underwater for extended periods of time (i.e., days to weeks), thus extending their work time. Saturation diving works on the premise that if a diver's tissues are in equilibrium with the surrounding water, then the decompression time will not change for the length of time spent underwater. Undersea habitats (also known as undersea laboratories) take advantage of this principle by providing a dry living space on the ocean floor for small teams of divers, known as ‘aquanauts.’ Aquanauts conduct research dives in the ocean near the habitat during the day, and, instead of coming to the surface after diving, return to the undersea laboratory to eat, rest, and sleep.

Aquarius
Today, NOAA’s Aquarius undersea laboratory is the only undersea habitat in the world devoted to science. The habitat, owned by NOAA and managed by the University of North Carolina at Wilmington, is located 64 feet below the surface at the base of a coral reef in the Florida Keys National Marine Sanctuary. Aquarius provides life support systems that allows up to four scientists and two technicians to live and work underwater, in reasonably comfortable living quarters for missions lasting up to 30 days. The Aquarius habitat increases working bottom time to nearly ten times over what scientists typically obtain using conventional surface-based diving techniques. At the end of each mission, aquanauts go through a 17-hour decompression, where the pressure inside Aquarius is slowly reduced from the pressure at the habitat's storage depth of 50 feet (ambient) to surface pressure, allowing the divers' tissues to regain surface equilibrium. The habitat is then repressurized to ambient depth, and the aquanauts are able to don scuba gear, swim out of the habitat, and ascend to the surface as if they had just performed a short dive to 50 feet. Additional advantages provided by the Aquarius include sophisticated power and communication capabilities. Scientists have email, telephone and video conferencing capability to anywhere in the world. Aquarius successfully supported more than 90 missions between 1993 and 2005.

OBSERVATION TOOLS
Last, but not least, NOAA uses technologies that collect data from and about the ocean. Some are tools (such as sondes, CTDs, and drifters) provide specific information about the ocean environment. Others are instruments (such as satellites) that provide generalized data from which a wide range of observations can be made. The information gathered from these instruments helps NOAA learn more about the Earth's oceans.

The Future
Over the past few decades, NOAA has significantly increased the nation's understanding of the oceans. Advances in technologies used to conduct underwater research and ocean exploration have revolutionized the way we explore the ocean. Likewise, the nation and the world are increasingly aware of humans' dependence on the oceans for healthy fisheries, clean habitats, and the potential to discover new medicines and answer questions about global climate. Yet, scientists and ocean explorers have only gotten a small glimpse of what the ocean has to reveal.

Relevant Web Sites
Undersea Technology: Tools for Research

Technology to Research the Ocean Depths

Ocean Exploration Technologies

Technologies and Capabilities for Ocean Research and Exploration

NOAA Ocean and Atmospheric Research

NURP Research in the Spotlight

NOAA Ocean Exploration

NOAA’s Underwater Technology B-Roll

NOAA Ocean Explorer: Technology Gallery

NURC/UNCW RESEARCH SYSTEMS AND TOOLS

NOAA National Undersea Research Program (NURP) Album

NOAA’S OCEAN EXPLORATION TECHNOLOGIES

Media Contact:
Jana Goldman, NOAA Research, (301) 713-2483 x 181