are investigating coral reefs at the world's only undersea laboratory
dedicated to marine science, called Aquarius.
The lab allows
the scientists to live and work on the seafloor, giving them longer
blocks of time to study reefs than conventional scuba diving would
you're a coral reef biologist, you've got to dive. You've got
to spend time in the environment that you're studying. And conventional
scuba diving is really limited. You work from the surface; you
have maybe an hour a day. Imagine trying to do your job if all
you had was an hour a day," Steven Miller, director of the
University of Wilmington's National Undersea Research Center,
told the NewsHour.
facility -- owned by the National Oceanic and Atmospheric Administration
and operated by the University of North Carolina at Wilmington's
National Undersea Research Center -- is currently located 9 miles
southwest of Key Largo, submerged 63 feet on a sandy patch in
the Florida Keys Marine Sanctuary next to Conch Reef.
studying in Aquarius, nicknamed "aquanauts," can work
underwater for up to 14 days and dive for up to nine hours a day.
Aquanauts are able to avoid the restrictions of conventional scuba
diving through saturation diving, a diving technique that allows
nearly unlimited time to work underwater.
dive is "an exposure of sufficient duration so that the diver's
tissue gases reach equilibrium with the pressure environment,"
according to NOAA's Diving Manual. Saturation diving allows aquanauts
to live and work at ambient pressure, (the pressure at Aquarius'
working depth is 2.5 times surface pressure) for months at a time.
is based on the fact that after 24 hours at any working depth,
a diver's body becomes saturated with dissolved gas from the environment.
Once saturated, decompression -- the time necessary to return
the diver progressively back to surface pressure -- is the same
regardless of the amount of time spent underwater.
Aquarius essentially allows you to extend the time at depth indefinitely
so you can make much more detailed observations. And this makes
a tremendous difference in our level of understanding how things
work," John Ogden, director of the Florida Institute of Oceanography,
told the NewsHour.
At the conclusion
of an Aquarius mission, aquanauts undergo a 17-hour decompression
period where the pressure inside Aquarius is gradually reduced
to meet surface pressure. The aquanauts then swim to the surface
and are taken back to shore.
yellow undersea lab consists of three main system components:
the Life Support Buoy, the baseplate and the "habitat"
The LSB moored
above Aquarius contains compressors, generators and a communication
tower that provides audio, video, and data transmissions between
Aquarius and shore. It contains Aquarius' oxygen hoses and power
and communication lines.
baseplate provides a stable platform for Aquarius. Each of its
four legs can adjust for leveling Aquarius on uneven seafloor
terrain by using hydraulically driven screw jacks. The laboratory
is then mounted about 47 feet off the seafloor. This operating
depth is called the "hatch depth."
live and work inside the Aquarius "habitat" module,
a 43-foot-long, 9-foot-wide structure that can house a six-person
crew and can operate at a depth of up to 120 feet. The living
quarters contain a sleeping area, kitchen, computer workstations
and life support controls. Modes of communication with the outside
world include e-mail, telephone and video conferencing.
enter the habit through a nonpressurized 8-foot-long "wet
porch," which provides access from the sea to Aquarius. The
wet porch remains open to the ocean, and water remains outside
Aquarius by the equivalent air pressure inside.
Next to Aquarius
is the Gazebo, which provides a safe place in the event of an
emergency within the habitat. The Gazebo has an enclosed aluminum
roof with 60 cubic feet of air, which is enough room for six aquanauts.
In Key Largo,
a shore-based Mission Control contains a "watch desk"
linked to Aquarius via a telemetry system.
and two technicians stay aboard Aquarius during a single mission,
but the support crew is much larger.
to Jim Leichter of the Scripps Institution of Oceanography, "There's
a very large support crew. And so when you're out diving, there's
a constant activity of equipment being brought down from the surface."
scientists at Mission Control oversee each mission.
launch in 1988, more than 200 scientists have stayed in Aquarius
on over 50 missions designed to better understand our oceans.
Aquarius allows scientists to do "the best possible science"
by seeing a larger view of the coral reef system. Research proposals
are submitted to the program annually and are chosen through a
includes pollution studies, water quality studies, human effects
on coral and ultraviolet light's damaging effects on reefs.
have stayed in Aquarius to help prepare for journeys into deep
space. And doctors with NASA's Extreme Environment Mission Operations,
or NEEMO, have studied the possibilities of remote surgeries using
Aquarius' telecommunication technologies.
aboard Aquarius are studying ways to preserve coral reefs, working
to steadily build their knowledge of these complex ecosystems.
20 percent of the world's coral reefs have been destroyed, and
in the United States Caribbean and Gulf of Mexico region, 56 percent
of the reefs are in critical condition, according to the 2004
Status of the Coral Reefs of the World report written by the Global
Coral Reef Monitoring Network and the International Coral Reef
not like there's a magic bullet, a silver bullet if you will,
that once we find this one spectacular piece of information we're
going to save the reefs. That won't happen. What we need is a
long-term sustained effort at trying to understand all the factors
that affect the condition of the reef," Miller said.
here to visit NOAA's Aquarius Web site.)
By Katie Mulik, NewsHour