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In the Pacific Ocean, off the coast of British Columbia re two underwater observatories -- NEPTUNE
and VENUS They use the latest technology to make amazing discoveries about the largely
unexplored world beneath the waves. Discover the ocean. Understand the planet.
Welcome to "Ocean Alive!"
Hello, I'm Sarika Cullis-Suzuki. As an ocean scientist, I am fascinated about the underwater
world. Today, researchers are using new technologies to understand our ever changing and fragile
Northeast Pacific Ocean. I'd like to share with you some of their exciting discoveries.
This is "Ocean Alive!"
As we embark on our exploration of the vast ocean, let's consider how we can gather information
about a place that is often deep, dark and dangerous. Let's find out how ocean observatories
let us visit this mysterious world.
Ocean Networks Canada is a unique facility in the world. And it's unique because it is
a place where we can measure the changes in the ocean 24/7 in the Northeast Pacific and,
what is called here, the Salish Sea. Ocean Networks Canada operates NEPTUNE and VENUS
- 2 cabled observatories off the west coast of British Columbia. The observatories supply
power and internet connectivity to a broad suite of sub- sea instruments from the coast to the
deep sea. They support research on complex ocean and earth processes in ways not previously
possible.
So it's very different from other kinds of observatories, it's not one instrument at
one time in one place in the ocean it's persistent in a place where the ocean changes over these
instruments and we have instruments in the water column, on the seafloor and beneath the
seafloor to really understand that incredibly connected system.
These underwater labs are bringing us huge volumes of data. What are researchers doing
with all this information?
Ocean Networks Canada has a pretty broad range of science disciplines that are working on
the data and instruments from both NEPTUNE Canada and VENUS and those are related to
everything from earthquakes to tsunamis to ecosystems.
We are also studying marine mammals, we are studying sounds in the ocean we are studying
wave energy and how that impacts things like release of gas hydrates on the seafloor.
It is one of the most diverse facilities of its kind studying almost every aspect of
the oceans and the seafloor beneath.
We were not only here to support excellent science, but we were also here to realize
benefits for Canada. It relates to how it helps to stimulate commercial opportunity
and how the public can better understand what we're doing and how the science can inform
their knowledge of the ocean.
The role of the center is to help grow the ocean technology sector in Canada and we do
that through mechanisms like the technology demonstration facility where we help develop
new sensor technologies and also we help develop new ocean observing systems both within Canada
and internationally.
One of the major accomplishments obviously has been to build the system. There were many
doubters quite frankly who said this can't be done.
The fact that we've done it, the fact that we've been operating now successfully with
high reliability of most of those systems for the last several years is a testimony
obviously to what has been accomplished.
We are so excited about the accomplishments of Ocean Networks Canada but we have aspirations
to see it grow even further. Already the world is coming to the University of Victoria and
Ocean Networks Canada to understand how observatories operate and we know that people are interested
in putting these observatories in virtually everywhere in the world.
Looks like there's a lot going on at the lab. Coming up next, let's put ONC to work and
see what we can discover about the ocean.
Here on the West Coast we hear a lot about tsunamis. As we know from recent events in
Japan and southeast Asia, tsunamis can be incredibly destructive.
So, what exactly are tsunamis and where do they come from?
A tsunami is what we refer to as a body wave. It affects the entire water column in an ocean
or lake. It is essentially is a wave phenomenon in that energy is propagated away from a source.
I kind of, because they've been so destructive, refer to them as stealth killers.
The seismic ones generated by earthquakes when you displace the bottom. Off Sumatra
in 2004, that huge tsunami that was generated there was displacements of five to ten metres
in the bottom where suddenly the bottom goes up on one side and down on the other and all
that water, two thousand metres of water, is displaced. Huge waves are generated. So
that's earthquake generated tsunamis, seismically generated tsunamis. They happen everywhere
in the world.
The other kind are landslide generated tsunamis. So a failure of the coast line or some kind
of big slump that fails and it pushes the water ahead of it as it fails or a mountain
falls into the water.
But about eighty percent of the big tsunamis in the world are generated in the Pacific
Ocean and the reason that tsunamis occur in these environments is that's where big earthquakes
occur, along the Pacific Ring of Fire. It's called that because these earthquakes are
also associated with active volcanoes.
We get these very explosive, fiery eruptions that occur because these plates are in contact
with one another and generating the forces that can create both earthquakes and volcanic
eruptions.
The speed of a tsunami is basically set by the depth of the ocean so if we use an average
depth of the ocean about five kilometres it's basically the speed of a jet. So that's 700-800
kilometres per hour.
You're on an aircraft coming from Japan for example towards Canada during the 2011 Japanese
tsunami your jet plane would just be able to keep up with that wave as it crossed the
ocean. It took it nine hours and fifty-seven minutes to get to Bamfield on the west coast
of Vancouver Island.
So this massive wave can move at the speed of a jet! What are the odds of a tsunami landing
here? And if one does, what should we do?
The likelihood of a tsunami coming to Vancouver Island is actually very good. We live in a
very seismically active region and so we are at a high risk of tsunamis. So any Pacific
based earthquake, and large Pacific based earthquake could cause a tsunami which could
impact British Columbia's Pacific coast.
We have developed with Rick Thomson very very precise sensors on the bottom of the ocean
that actually measure the actual pressure of the water which is really equivalent to
the height and we can precisely measure to sub millimeter detail in 3 kilometers
of water how high that wave is.
And so with those sensors we can then begin to use models to predict the speed and direction
and the height of the wave that will impact our coast.
If there is a mega thrust earthquake off our coast we will have a major tsunami and we
want to be able to provide much more direct warning. Now we wouldn't be doing this directly
we have to work with our emergency management teams here in British Columbia, but that's
the direction we want to go in.
The information and data that's collected from Ocean Networks Canada helps emergency
managers to understand what kind of tsunami might be coming in at any given time.
We have the ability with the technology we have, to do an early detection of an earthquake
when it first hits. We may be able to give places in Vancouver and Victoria a thirty
to forty second warning of major ground shaking hitting.
That's a lot. People say well that's not very much but it can turn off a valve, it can stop
trains, it can set off an alarm in schools. So there's many things we can do with that.
So we're working with a team of people in British Columbia over a five year time period to see if we can implement
something like that.
I think the most important thing about tsunamis is understanding your risks, where you live,
where you work and where you play. So if you're travelling to an area that has tsunami risks
to understand that there is a tsunami risk and then to understand what you would take,
what actions you would take to keep yourself safe in the event of a tsunami.
You're walking the beaches in Tofino and there is a big earthquake, don't even wait for any
warning just go to higher ground because you're going to have about half an hour at most three
quarters of an hour before that tsunami hits and it's going to be big on the outer coast.
Today, we've learned how underwater earthquakes generate tsunamis... next let's find out what
happens at underwater volcanoes.
Few people know that 300 kilometres off the West Coast of Vancouver Island, lies a
chain of underwater volcanoes, known as the Juan de Fuca ridge. Part of this region was
established as a Marine Protected Area in 2003. This is where we find deep-sea hydrothermal
vents.
So hydrothermal vents are located at mid ocean ridges. So picture it as seams along
a baseball and when you go away from these seams it's almost like the desert. There is
not really much life there. It's called the abyssal plain so it just looks like mud flats
going on and on and on.
When you get closer to these little seams on the baseball at the hydrothermal vents
you see an abundance of life.
Hydrothermal vents form when two plates are separating away from each other and new crust
from the Earth's centre starts migrating upwards. You'll have water that percolates through
this really super-hot crust and from pressure and both temperature it'll come back up and
start precipitating these minerals out, once it reaches that cold seafloor.
So you'll get these precipitations slowly start forming these hydrothermal chimneys
and once the temperatures as well as the right conditions are available for new animals they'll
start colonizing these hydrothermal vents.
So we can go from a volcanic eruption that essentially flattens everything to the beginnings
of a vent ecosystem with a number of species within less than a year.
They're at depths usually between fifty and one hundred metres to up to four thousand metres
below the sea surface. So basically no sun can penetrate these environments. It's in
complete darkness.
The ambient seawater is usually about two degrees at those depths but at these hydrothermal
vents you're getting these just like picture underwater volcanoes, they're spewing out these
hot vent fluids that are up to four hundred degrees Celsius in some cases.
They're extremely toxic so you have hydrogen sulfide, carbon dioxide, methane, so for you
and I there's no way we'd be able to survive at these hydrothermal vents.
Wow, pretty extreme conditions at these deep-sea vents. How can anything actually live there?
You're on an underwater volcano where there's absolutely nothing alive and then boom you
come across this little oasis of life with colour, reds, blues and animals you've never
seen before. Everything we brought up had never been seen by a scientist before.
Bottom few hundred metres of water contains millions of larva of vent animals that have
been released by vent ecosystems in the surrounding area. These larvae are constantly looking for,
urgently looking for, a new place to settle down. They detect the vent environment, they
come in, settle down on the seafloor and transform into juveniles and then adult animals. So
they can colonize in a matter of months.
Most of the animals that live there are unusually tolerant of high temperatures, toxic hydrogen
sulfide and even heavy metals. There's a really limited number of species that can colonize
hydrothermal vents but those that can really cut it do really well. We find incredible
biomass in this environment even though there are very small number of species.
Some of the more common animals at hydrothermal vents in the North Pacific are the giant tubeworms.
These are large worms that can be up to 2 metres in length. They have no mouth, no digestive
system. The only way that they can exchange anything with the outside world is through
their gills.
They survive by the symbiotic relationship with bacteria and essentially what they do
is uptake this bacteria into an internal organ called the trophosome and the trophosome houses
all these bacteria. And if you have seen a picture of a tubeworm they have these red
bushy plumes at the anterior portion of their body and they uptake these dissolved gases
which are toxic to you and I so it would by hydrogen sulfide, carbon dioxide as well as
oxygen and essentially this feeds the internal bacteria that provide the sole and only nutrition
for the tube worms.
Hydrothermal vents are a highly ephemeral environment and by ephemeral I mean it's very
dynamic in vents are shutting off and then turning back on and starting up in a new location
or even vents can shut off and then turn back on again at the same location later on.
So life itself at these vents that are turning off usually end up collapsing or dying but
then you'll see them pop up at these new hydrothermal vents and recolonize new areas. So it's very
dynamic and its constantly circling around as they die out they'll recolonize new vents
again.
We've learned about hydrothermal vents and the unique species that are found there. From
the exotic, now let's take a look at animals you might have seen before... whales.
The coastal and offshore waters of British Columbia are home to many species of whales.
Let's take a closer look at the world of whales and in particular how we study them.
A whale for example with an orca it only spends probably five percent of its time at the sea
surface and since that's the only time we can really see them we are pretty limited
in terms of what we can, what we can study. They just come up, they take a breath and
then go back down so we can't really study much about their behaviour just visually.
So what we use is passive acoustics and passive acoustics means you just listen to what they
are doing down there.
We use hydrophones to study orcas because they can get a different kind of data then
photo identification would get or visual surveys would get and also because it isn't possible
to do visual surveys for such an extended amount of time or for example at some moments
of the year when the weather is not very good to go out at sea on boats.
The large baleen whales like the blue whales and the fin whales, those animals produce
sounds that are almost below our hearing as human beings and but the low frequency hydrophones
can detect them at really low ranges.
The high frequency hydrophones are looking for different acoustic signatures. They can
detect the signatures of naval sonars for example or dolphins or orcas or sperm whales
and shipping noise.
Makes complete sense. If the whales are spending 95% of their time underwater then hydrophones
are a great way to gather information. So what have we discovered from this research?
Since we started using hydrophones we have gained valuable knowledge about orcas. The
first one that I can think of is their vocalizations and discovered that they have different dialects.
That was kind of a revolution in the acoustic science of killer whales.
The hydrophone data is used by the whale researchers to understand when are the whales coming through
the area so obviously they need their presence and doing something. Then they try to understand
what are the whales doing at that time. Are they socializing? Are they just gathering
together? Are they hunting? Are they looking for prey? Are they looking for food?
Other than that some studies have been made using hydrophones to study over time how the
amplitude changes of their calls over time regarding with environmental noise or background
noise or anthropogenic noise.
The ocean is getting to be a noisier and noisier place and that's something we are starting
to get concerned about.
Sounds like we have discovered what most of us could have guessed -- the ocean is getting
noisier. So what does this mean to the whales and what can we do about it?
The kinds of sounds that disturb orcas in particular are sounds that are continuous
in natures and broadband we would say that cover a lot of frequencies. So big problem
is ship noise and boat noise. Shipping noise, noise produced by large ships is extremely
loud and it goes on for long time as a ship passes. So it can blot out the soundscape
easily for you know half an hour when as far as killer whales go are concerned every time
a ship goes by. Smaller boats can be much noisier really for their size than large ships,
outboard motors in particular are bad.
Pile driving or even seismic exploration are all increasing the noise levels in the ocean
in which the whales have to live. They have to accommodate whether they have to speak
louder or find other dialects to communicate, is all part of the research we are undertaking.
The consequences of noise for killer whales is that it effects their communication in
particular. It, we call this masking, it can simply block out their communication or make
it much harder for them to communicate over longer distances. So that could have a variety
of impacts from just affecting the cohesiveness of pods to affecting the way that pods interact
with each other.
Sound also affects the ability of killer whales to use echolocation. They have to hear these
echolocation sounds are quite quiet compared to the sounds they are producing. So killer
whales can only compensate by making their sounds louder and they can only do that to
a certain extent.
We really need to understand the impacts of what we're doing in the ocean to make sure
that we modify our behaviour slightly so that we have less of an impact on some of these
endangered species or whales in general.
Today we had a chance to take a closer look at whale research. As you can see, technology
is very important part of ocean science. Coming up next, we'll hear about what the future
holds for ONC.
Before we wrap the show I had one more question for the team at Ocean Networks Canada. Guys,
what's next?
What's next for Ocean Networks Canada is Smart Oceans BC. It's an initiative that we've started
here at Ocean Networks Canada for taking the technology from NEPTUNE and VENUS and moving
it to locations in the northern coast of BC and the northern strait of Georgia and we're
taking the data from those systems through our powerful data management system Oceans
2.0 and using high-performance computing provided by IBM Canada and combining those with models
to actually provide new information for a wide range of stakeholders communities...industry...and
scientists.
Smart Oceans BC has 3 important areas that we'll be delivering on. One is marine safety..for
example we'll be able to provide information about where marine mammals are located so
that ships can avoid hitting them.
The second one is environmental monitoring...providing a benchmark so that we can assess how things
are changing as the coast develops.
And the third is public safety..so we'll be providing notifications developed in partnership
with IBM Canada for emergency managers for example. so we can provide them with information
about 30 to 90 seconds ahead of a ground-shaking earthquake.
Our major funder for this initiative—for Smart Oceans BC...is Western Economic Diversification
They've provided a significant amount of the funding to purchase the equipment needed to
install Smart Oceans BC in the north and northern Strait of Georgia.
We're also partnering with IBM Canada and they're providing high-performance computing
so we can actually take the data and develop notifications and information not only for
the public -- for government and and industry -- but we'll be able to take information that
's local to coastal communities and allow them access -- free access -- to the ocean
right at their doorstep.
Well, clearly the future looks exciting at Ocean Networks Canada! But how does technology
help keep our ocean alive? While data from the deep allows scientists to gain new insights
and make discoveries, it is what we choose to do with this knowledge that will truly
make a difference.
I'm Sarika Cullis-Suzuki. Thanks for joining us.