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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 initiativefor 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.

In the Pacific Ocean, off the coast of British Columbia re two underwater observatories -- NEPTUNE

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オーシャンアライブ!フルプログラム (Ocean Alive! Full Program)

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    richardwang に公開 2021 年 01 月 14 日
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