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Exploring the Underwater Environment

Aug 23
A NOAA Diver collects coral samples underwater

NOAA Diver Randy Kosaki collects black coral at Necker Island in the Northwestern Hawaiian Islands. He is wearing open circuit technical diving gear.

The ocean covers more than 70% of the surface of our planet and yet it still remains largely unexplored. Inside its mysterious depths lie discoveries that can expand our thinking and improve our lives in ways that are yet unknown. Based on our level of technical development, humans have been able to explore various depths, and at NOAA, we make use of a wide variety of ways to gather the data that our scientists need.

Divers and submersibles can both play important roles in our quest to understand what lies beneath. Divers using traditional open circuit scuba explore depths of up to 30 meters (about 100 feet), while submersibles have allowed us to study marine life and objects down to 150 meters (500 feet) and below.

The area of the ocean least known is that area that cannot be reached by traditional open circuit diving and which submersibles have not explored. The level between 30-100 meters is now being explored by NOAA divers using open circuit technical diving and closed circuit rebreathers.

Unlike traditional open circuit scuba, technical diving can make use of mixed breathing gases to allow divers to reach deeper depths and shorten the length of decompression stops that are needed to acclimate the diver when returning to surface pressure. With closed circuit rebreathers (or CCRs), not only can divers mix their own breathing gas at depth, they can also recycle their exhaled gases to extend the amount of breathing gas that is available to them during their dives.

At NOAA, divers conduct safe operations using all these techniques. Who knows where we will go next?

Two NOAA Divers seen from below descend to a depth of 300 feet.
Robert Whitton/Bishop Museum/NOAA

NOAA Diver Brian Hauk and Reciprocity Diver Richard Pyle descend to a depth of 300 feet (an area also referred to as the twilight zone) on Pioneer Bank during research activities in the Papahānaumokuākea Marine National Monument. They are using closed circuit rebreathers.



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Reviewed: May 28, 2019. Contact us with page issues.

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