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ALAN
ALDA Hello and welcome to Scientific American Frontiers. I'm Alan
Alda. It's said that the oceans, which cover more than two thirds
of the earth's surface, are less familiar to us than the surface of
the moon. If you consider the volume of the oceans, it's actually
more than ninety percent of the habitable part of the earth that we
don't know too much about. The main reason for our relative ignorance
is simply that the deep ocean is an absolutely forbidding environment.
It's pitch dark, extremely cold and with pressures that are like having
a 3,000-foot column of lead pressing down on every square inch --
which does sound pretty uncomfortable. In this program we're going
to see how people finally made it to the ocean floor, and we'll find
out about the scientific revolutions they brought back with them.
We're going to go diving in the Alvin, the little submarine that did
so much of the work. And we're going to glimpse the future, as Alvin's
successor takes shape in a small seaside town on Cape Cod. That's
coming up in tonight's episode, Going Deep.
INTO
THE DEEP
ALAN
ALDA (NARRATION) Woods Hole, Massachusetts. It's one of the picturesque
seaside towns that draw the tourists to Cape Cod each year. But
few seaside towns have what Woods Hole has. For 70 years it's been
home to the Woods Hole Oceanographic Institution an organization
that does nothing but study the world's oceans. While the tourists
on Main Street are thinking about fried clams, all around them the
folks at the Institution -- or WHOI, as it's universally known --
have other things on their minds. Like this, for instance. It's
the submarine that's going to be exploring the world's oceans for
the first half of the 21st century. The new sub is to replace this
one the Alvin. Arguably the most successful deep-diving sub
ever built, Alvin's still at work after 40 years, but now getting
hard to maintain. And, no it's not named after a chipmunk,
although oceanographers think it's just as cute. It's actually named
for Allyn Vine, a WHOI scientist who championed the cause of ocean
exploration. In the summer of 1964, Alvin made its first tentative
dives in the shallow waters around Woods Hole often with
Allyn Vine on board. The essential component of any deep-dive sub
is the part you can't see here the massive pressure hull
that protects the crew.
BOB
BALLARD The first submarine ever built in America was the Turtle
.
ALAN
ALDA Oh, really?
ALAN
ALDA (NARRATOR) Bob Ballard started working with Alvin at WHOI in
1967. This sister ship to Alvin has a pressure hull that's a steel
ball, about 6 feet in diameter inside, hidden in the structure.
There's a single small hole in the top of the ball.
BOB
BALLARD This is the hatch. Two inches thick,
ALAN
ALDA So, what keeps the water from going in here?
BOB
BALLARD Well it's actually tapered. If you look at the hatch, it's
like a porthole, the pressure pushes them down. In fact, you're
most vulnerable at the surface. That's the most dangerous time because
you don't have the pressure seating it. Alright, well let's get
down inside here. So watch your step.
BOB
BALLARD Absolutely a sardine...
ALAN
ALDA Oh my God! It's tiny!
ALAN
ALDA (NARRATION) In 1869, a hundred years before Alvin's launch,
the French writer and ocean sailor, Jules Verne, published his classic
story of the renegade scientist who travels the world's oceans in
his fabulous submarine, Nautilus. None of Captain Nemo's technology
existed at the time, of course, although in Hollywood's 1916 version
the self-contained diving suits were a genuine technical advance.
The adventures of Captain Nemo and his crew were an inspiration
for generations of ocean explorers, including Jacques Cousteau and
Bob Ballard. While some features of the Nautilus brilliantly foreshadowed
later developments, Jules Verne did skip over the challenges of
water pressure. Submarines, like the Nautilus, capable of accommodating
large crews, developed rapidly during the Second World War. Yet
water pressure limited the best of the German U-boats to a depth
of about 700 feet, and today's large submarines can go no deeper
than a thousand or so. It was Otis Barton, an engineer from Massachusetts,
and his collaborator, William Beebe, who first solved the problem
of how to reach extreme depths. The solution was to dive in a small,
massive sphere they called it a bathysphere. A spherical form
offers the most effective resistance to the crushing pressures at
depth. In a series of dives off Bermuda in the 1930s, they shattered
the existing depth record of 525 feet, established by a diver in
an armored suit. The bathysphere was simply lowered from a barge,
a risky business since any fault in the cable would lead to a fatal
plunge to the bottom. It was the peculiar subs called bathyscaphs,
conceived by the Swiss balloonist Auguste Piccard in the 1930s,
which finally reached the deepest part of the ocean the 35,000-foot
Challenger Deep off Guam. A huge tank of gasoline provided flotation,
so you didn't need a suspension cable. Bathyscaphs were safer, but
very unwieldy, as Bob Ballard discovered personally.
BOB
BALLARD The front of the submarine came down and I'm looking at
it, and it's just the metal and everything, its just twisting in
my eyes, like a giant... just slowly, just very slowly, taking the
submarine and just ripping it open. And then I see av gas coming
out.
ALAN
ALDA What's that?
BOB
BALLARD That's the flotation gasoline. We ruptured our tank.
ALAN
ALDA How did this turn out? Did you live?
BOB
BALLARD Well here's what happened. We then, he dropped the whole...
then you could drop the whole door and he dropped ten tons. When
he saw that, I said "av gas!" When I yelled "av gas," he dropped
the doors open and we dropped ten tons. Now we're at 20,000 feet.
It's a six hour trip home and here's what happens. You're leaking
your gasoline and you start decelerating and then you start back
down. Well, they had in the sub a little calculator, you know one
of those little LED displays? Freezes up on a number? And so every
few seconds, it was telling you your ascent rate. Well ,there was
enough uncertainty in the calculation that it depended upon whether
you were an optimist or a pessimist. You could get whatever you
wanted out of those numbers.
ALAN
ALDA You didn't know whether you'd make it to the top before you
lost your gasoline which gave you the buoyancy?
BOB
BALLARD Exactly. And then you'd go negative. No one spoke. The most
silent experience I've ever had, and we all looked at those numbersÉ
ALAN
ALDA For six hours?
BOB
BALLARD For six hours. And we were decelerating, because we were
losing flotation. But we had enough to get home.
ALAN
ALDA (NARRATOR) Although Alvin has done some great science as
we'll see later it was originally built for the US Navy, and operated
by WHOI. Its first deep dive, to 6,000 feet, was to check out a
secret listening array off the Bahamas. Soon after that Alvin was
brought here, off the coast of Spain, to play a starring role in
a famous Cold War incident. In the 60s, B-52 bombers loaded with
live H-bombs, were always in the air. One such patrol, returning
to North Carolina, had a catastrophic collision with its aerial
refueling tanker. Seven crew members died, and four H-bombs plunged
to earth. Mercifully, they did not explode, and three were recovered
on land. The fourth, though, was 2,000 feet down in the Mediterranean.
Alvin found the bomb, after 19 dives, by following a long gouge
in the sea floor, spotted by the WHOI crew. The gouge led to the
bomb's parachute. This film has never been shown before, by the
way. Alvin's remote control arm couldn't recover the bomb, but it
did help guide a secret new Navy robot to snag the parachute and
haul the bomb up. There had always been doubts whether Alvin would
really turn out to be useful but not anymore. The incident showed
that people could routinely reach unprecedented ocean depths and
so could robots. This tension between manned and unmanned deep diving
has continued to this day. A unique ship made from these surplus
Navy pontoons was to cause a near disaster for Alvin, as well. Alvin
was carried to dive sites on Lulu, then lowered into the water between
the pontoons, suspended on steel cables. In 1968, this was the result.
A suspension cable on Lulu had snapped, and Alvin had fallen into
the sea with the three crew members inside, and the hatch open.
The sub sank in 60 seconds, but not before the crew scrambled or
were pulled to safety. After seven months, a secret Navy camera
system -- towed by this ship, the Mizar -- found the wreck. Another
deep-dive sub, the Aluminaut, was brought in. The plan was for the
Mizar to dangle a nylon rope down to the Alvin. Then the Aluminaut
would use its remote control arm to hook the rope to the wreck.
It took two trips over three months, but they finally did it, and
Alvin was winched up 5,000 feet from the floor of the Atlantic.
In our next story, we'll look at some of the important science results
that Alvin went on to achieve over the next three decades. But first,
take a look at the famous sandwich that came up in the Alvin in
perfect shape after a year on the bottom. It led WHOI scientists
to look closely at slow decomposition at depth, and then argue against
the idea of deep-ocean disposal of waste. It was a great service
performed by one sunken sub, and one baloney sandwich.
DEEP
SCIENCE
ALAN
ALDA (NARRATOR) We're in the eastern Pacific, near the Galapagos
Islands. We're going to go on a typical deep science dive, into
the Galapagos Rift. The Alvin's made thousands of such dives over
the last three decades.
TECHNICIAN
Have a good one. Sealing the hatch.
RALPH
HOLLIS Hatch is secure.
ALAN
ALDA (NARRATOR) But this dive, which our cameras filmed a few years
ago, is in many ways the classic Alvin dive. It was here in 1977
that people, for the first time, gazed out from the sub at a kind
of life we never knew existed.
RALPH
HOLLIS Hatch is closed, oxygen on, CO2 scrubber on, ID light on.
Request permission to dive.
CONTROLLER
Roger. You're clear to dive. Depth of the target 2485. Clear to
dive.
RALPH
HOLLIS Roger Alvin diving.
ALAN
ALDA (NARRATOR) We're going down 8,000 feet, although the metal
ball that's protecting us can safely reach 15,000. It will take
two hours to reach the bottom.
RALPH
HOLLIS My depth is 1620, one six two zero. 1620 one six two zero.
ALAN
ALDA (NARRATOR) The acoustic radio echoes through the ocean.
RALPH
HOLLIS Everything looks normal, Jim, so far.
JIM
CHILDRESS OK. We'll be on the bottom before long.
RALPH
HOLLIS 600 meters to go.
ALAN
ALDA (NARRATOR) We're diving on a part of the ocean ridge system
an enormous undersea mountain range that snakes around the globe.
In the 1960s we realized the mountains are actually volcanoes, which
create the earth's crust. Then in the 70s, deep-diving subs like
the Alvin began to visit the ocean ridges.
RALPH
HOLLIS A2, this is Alvin. At the bottom. Depth is 2507, two five
zero seven, ambient temperature, two point zero four nine.
ALAN
ALDA (NARRATOR) First, we're gliding over lava fields. Then the
water begins to warm up. And we seeÉ giant clams. They were first
glimpsed in 1976, by a remote camera system from the Scripps Institution
of Oceanography. The next year, in a WHOI expedition led partly
by Bob Ballard, Alvin came down and found the clams, found hot water
vents -- and found a whole new kind of life on earth. Clustered
around the underwater volcanic springs -- called hydrothermal vents
-- was an array of unknown life forms, thriving in the warm currents.
Tube worms, clams, mussels, crabs and fish. At first, scientists
couldn't figure out how these things survive. Up above, all life
depends on sunlight and photosynthesis but here there is no sunlight.
It turned out that life here depends on kinds of bacteria that were
new to science. They live on the energy of the earth itself, consuming
hydrogen sulfide gas that's dissolved in the water that flows from
the vents. This may be how life on earth began. The scientist on
our dive, Jim Childress from UC Santa Barbara, does not always look
out the window, as you might expect. Instead, he's watching a TV
monitor while the pilot, Ralph Hollis from WHOI, collects the samples
Jim wants. It makes sense for professional pilots to run the sub's
systems, but it can be frustrating for the scientists not to see
directly what's happening.
JIM
CHILDRESS Where are you, sort of right where the tube comes out
of the rocks?
RALPH
HOLLIS Well, I'm up to the yellow mark, into the fissure where the
tube worms are.
ALAN
ALDA (NARRATOR) How pilots and scientists can best work together
on the ocean floor is going to change in Alvin's replacement.
RALPH
HOLLIS A2, Alvin. Request permission to surface. Request permission
to surface.
CONTROLLER
Roger.
ALAN
ALDA (NARRATOR) To surface, the Alvin drops a thousand pounds of
steel ballast maybe right on top of a biology sampling area.
RALPH
HOLLIS Both weights away.
ALAN
ALDA (NARRATOR) Later on we'll talk about plans for new working
conditions, and ballast, in Alvin's replacement. The objective,
though, will remain the same take scientists down, and get them
back, with their amazing finds. In 1979, Alvin made another historic
find, in an area called the East Pacific Rise, off Baja, California.
They called them Black Smokers chimneys spewing out clouds of
mineral-rich water, so hot that it must have come from deep in the
earth's crust. This explained why the sea is so full of minerals.
BOB
BALLARD The seawater, which is under pressure, goes right down into
those cracks, goes down into the magma chamber. The magma chamber
is hot -- 1400 degrees, 1200 to 1400 degrees centigrade. And so
it heats up the water, and then the water begins to interact with
the magma chamber, and it changes its chemistry.
ALAN
ALDA Now does the water turn to steam?
BOB
BALLARD No, it can't because of pressure. It turns into superhot
water.
ALAN
ALDA Superhot water which means it stays É
BOB
BALLARD Liquid. ALAN ALDA Liquid, but it's really...
BOB
BALLARD Really hot. And its now full of chemicals that it didn't
have before. And its those chemicals that are coming out of the
black smokers that are responsible for the chemistry of the world's
oceans. In fact we now realize that the entire volume of the world's
oceans is going inside the earth and out, every six to 8 million
years.
ALAN
ALDA Every six to eight million years.
BOB
BALLARD The entire volumeÉ
ALAN
ALDA All the oceans in the worldÉthey all go down...
BOB
BALLARD Through this system.
ALAN
ALDA Under the floor of the ocean.
BOB
BALLARD Into the mountain range, and come up in the form of black
smokers.
ALAN
ALDA And it takes eight or ten million yearsÉ
BOB
BALLARD For the whole ball game. That's a lot of water.
ALAN
ALDA Well, of course.
BOB
BALLARD And that's what's caused the chemistry of the world's oceans.
And we didn't know that.
ALAN
ALDA (NARRATOR) Diving in Alvin is not the only way we've discovered
how the oceans and their inhabitants work, but it's been an amazingly
successful way. Next we'll see how the folks at WHOI think they
can make a better Alvin.
GREATER
DEPTHS
ALAN
ALDA (NARRATOR) We're back at WHOI on Cape Cod. Every three years,
Alvin has to break away from whatever ocean it's exploring, and
return home. Then it gets torn apart and overhauled. They say there's
not an original piece of the sub left. In 1973 the all-important
pressure hull was replaced with a titanium version that could go
twice as deep, to 15,000 feet. The white blocks are a special foam,
made of microscopic glass bubbles, that can withstand the pressure
of the deep ocean. It's what gets Alvin back to the surface you
just drop some weight, and the sub floats up. That's why the Alvin
is so safe no main ballast tanks needing pumps and valves to empty.
Barrie Walden's group at WHOI is responsible for designing Alvin's
replacement. He's checking out the Sea Cliff, a US Navy sister ship
to Alvin, retired in 1998. Sea Cliff could dive to 20,000 feet
5,000 deeper than Alvin but the basic design is the same. And
inside the cramped pressure hull, the drawbacks are the same too.
BARRIE
WALDEN When these submersibles were first designed, video was nowhere
near as capable as it is today. So the designers purposely wished
for the observers to have different views than what the pilot had,
so that they wouldn't be wasting the human eyeball, essentially.
So these viewports do not overlap. The observers can't see what
the pilot is doing. The new Alvin is going to be different than
that, in that the pilot viewport will still be in approximately
the same position, but the observers' viewports will be pulled around
to the front and raised a little bit, to give them the same sort
of view that the pilot has.
ALAN
ALDA (NARRATOR) This is the other way to explore the oceans. It's
an ROV remotely operated vehicle. Now that video is so capable,
ROVs can send high quality pictures through a fiber optic cable,
back to the control room on the ship. It's cheaper and safer than
sending people down. They can take samples, remotely, too. Next
will be AOVs -- autonomous vehicles that can find their own way
out and back. So why build another manned deep submarine?
BARRIE
WALDEN Whenever I find somebody that is a champion of the other
methods of doing this kind of work, the easiest thing I can do to
convince them that there is a place for manned submersibles is let
them make a dive. There are some benefits that you get from actually
being there, looking around in person, that you just don't get from
a cable-controlled vehicle, or a vehicle that gives you data a week
after it's recovered, kind of situation. Now, I'm not saying that
we should have nothing but manned submersibles. My argument really
is that we need at least one manned submersible.
ALAN
ALDA (NARRATOR) In the belief that that view is correct, computer
models and plywood and fiberglass are now getting together to create
Alvin's replacement. This is a mock-up of the pressure hull -- although
it won't be sliced in half. Bob Brown -- a former Alvin pilot --
heads up the design team.
BOB
BROWN Here you see the pilot's seat. The pilot will sit -- will
be a movable little chair. And he would sit like this, with his
viewport here. The blue around here indicates the actual size of
the viewport. The simulator viewport we have is much smaller. The
actual one will be bigger. We have a small pilot's desk here in
the middle, and this is something that he can look at by glancing
down when he's looking out the viewport.
ALAN
ALDA (NARRATOR) The hull diameter is about six inches larger than
Alvin's, inside. Combined with touch screen controls and miniaturized
electronics, that will give a much roomier cabin. But there'll still
be a few old-fashioned, clunky controls. BOB BROWN We do have, on
the switches above here, we have switches for vital systems that
are necessary for getting the submersible back to the surface.
ALAN
ALDA (NARRATOR) The sub will use the same tough glass foam as Alvin,
but it won't be dropping steel weights to surface. Instead it will
pump water out of ballast tanks. In an emergency, it will still
be able to jettison all kinds of parts to get back up. The biggest
change though, is the two scientists having their own ports to look
out front. All three people will be able to work cooperatively.
BRUCE
STRICKROTT Put your head up there. We're not going to be fighting
for space, are we?
ALAN
ALDA (NARRATOR) Current Alvin pilots, like Bruce Strickrott, come
in regularly to try out the mock-up. The new sub will go to 21,000
feet 6,000 more than Alvin. To have reasonable working time on
the bottom, it'll need to go down and up twice as fast. So this
sub will be streamlined, and it'll almost fly up and down, at an
angle.
BRUCE
STRICKROTT What will this feel like at 20 degrees nose down in the
descent?
BOB
BROWN Yeah, we'll have to, er...
BRUCE
STRICKROTT Make some sort of vertical backrest, or something BOB
BROWN Well, probably a chair back here, probably not even sit on
that, and he can have his chair back here for going up, and something
else for going down, to be determined yet. And these things can
be changed to allow for angles.
ALAN
ALDA (NARRATOR) The goal is, in three years, to have all this carved
in stone or rather forged in titanium. The sub will give scientists
routine access to 99% of the earth's ocean floor in a whole new
style.
BRUCE
STRICKROTT I think it's like the difference between a Motel 6 and
a Hilton. They're going to love it, are you kidding me? It's bigger,
they got more viewports, they get to look out front -- they never
get to look out front. They get benches to sleep on, on the way
up and down. How could they not like it?
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