WEBVTT

00:00:20.083 --> 00:00:24.166
In 1956, a documentary by Jacques Cousteau

00:00:24.459 --> 00:00:27.834
won both the Palme d'Or
and an Oscar award.

00:00:28.042 --> 00:00:30.918
This film was called
"Le monde du silence,"

00:00:30.930 --> 00:00:33.169
or "The silent world."

00:00:33.609 --> 00:00:38.860
The premise of the title was
the underwater world was a quiet world.

00:00:39.509 --> 00:00:42.029
We now know, 60 years later,

00:00:42.030 --> 00:00:45.901
that the underwater world
is anything but silent.

00:00:45.902 --> 00:00:48.911
Although the sounds
are inaudible above water,

00:00:48.912 --> 00:00:52.252
depending upon where you are
and the time of year,

00:00:52.253 --> 00:00:58.417
the underwater soundscape can be
as noisy as any jungle or rain forest.

00:00:58.422 --> 00:01:04.569
Invertebrates, like snapping shrimp,
fish, and marine mammals all use sound.

00:01:04.879 --> 00:01:07.800
They use sound to study their habitat,

00:01:07.801 --> 00:01:11.440
to keep in communication
with each other, to navigate,

00:01:11.441 --> 00:01:13.862
to detect predators and prey.

00:01:13.863 --> 00:01:19.191
They also use sound by listening
to know something about their environment.

00:01:19.192 --> 00:01:21.882
Take, for an example, the Arctic.

00:01:22.782 --> 00:01:25.993
It's considered a vast,
inhospitable place,

00:01:25.994 --> 00:01:28.442
sometimes describes as a desert,

00:01:28.443 --> 00:01:33.555
because it is so cold, and so remote,
and ice-covered for much of the year.

00:01:34.445 --> 00:01:40.245
Despite this, there is no place on earth
that I would rather be than the Arctic.

00:01:40.246 --> 00:01:44.104
Especially as days lengthen
and spring comes.

00:01:44.504 --> 00:01:48.914
To me, the Arctic
really embodies this disconnect

00:01:48.915 --> 00:01:54.296
between what we see on the surface,
and what's going on underwater.

00:01:54.586 --> 00:01:59.917
You can look out across the ice
- all white, and blue, and cold -

00:02:00.587 --> 00:02:02.306
and see nothing.

00:02:02.646 --> 00:02:05.295
But if you could hear underwater,

00:02:05.296 --> 00:02:10.359
the sounds you would hear
would at first amaze and then delight you.

00:02:10.919 --> 00:02:14.658
While your eyes are seeing nothing
for kilometers but ice,

00:02:14.659 --> 00:02:18.166
your ears are telling you that out there

00:02:18.167 --> 00:02:22.542
are bowhead and beluga whales,
walruses, and bearded seals.

00:02:23.542 --> 00:02:25.631
The ice too make sounds.

00:02:25.632 --> 00:02:31.022
It screeches, and cracks, and pops,
and groans as it collides and rubs

00:02:31.023 --> 00:02:34.373
when temperature,
or currents, or winds change.

00:02:35.123 --> 00:02:39.304
And under 100% sea ice,
in the dead of winter,

00:02:39.614 --> 00:02:42.145
bowhead whales are singing.

00:02:43.185 --> 00:02:45.375
You would never expect that,

00:02:45.376 --> 00:02:50.503
because we humans,
we tend to be very visual animals.

00:02:50.504 --> 00:02:53.336
For most of us, but not all,

00:02:53.346 --> 00:02:56.544
our sense of sight is
how we navigate our world.

00:02:56.545 --> 00:02:59.464
For marine mammals that live underwater,

00:02:59.465 --> 00:03:03.493
where chemical cues
and light transmit poorly,

00:03:03.494 --> 00:03:06.794
sound is the sense by which they see.

00:03:06.795 --> 00:03:10.915
Sound transmits very well underwater,
much better than it does in air.

00:03:10.916 --> 00:03:14.504
So signals can be heard
over great distances.

00:03:14.505 --> 00:03:17.689
In the Arctic, this is
especially important

00:03:17.690 --> 00:03:21.423
because not only do Arctic marine mammals
have to hear each other

00:03:21.424 --> 00:03:24.785
but they also have to listen
for cues in the environment

00:03:24.786 --> 00:03:29.176
that might indicate
heavy ice ahead or open water.

00:03:29.177 --> 00:03:32.695
Remember, although they spend
most of their lives underwater,

00:03:32.696 --> 00:03:36.557
they are mammals,
so they have to surface to breathe.

00:03:36.807 --> 00:03:40.748
They might listen for thin ice or no ice

00:03:40.749 --> 00:03:44.369
or listen for echoes off nearby ice.

00:03:45.289 --> 00:03:51.168
Arctic marine mammals live in a rich
and varied underwater soundscape.

00:03:51.169 --> 00:03:54.497
In the spring, it can be
a cacophony of sound.

00:03:54.498 --> 00:03:57.496
(Buzzing, whizzing, squeaking,
whistling, wailing sounds)

00:04:11.219 --> 00:04:14.293
But when the ice is frozen solid,

00:04:14.294 --> 00:04:17.892
and there's no big temperature shifts
or current changes,

00:04:17.894 --> 00:04:22.489
the underwater Arctic has
some of the lowest ambient noise levels

00:04:22.490 --> 00:04:24.239
of the world's oceans.

00:04:24.459 --> 00:04:25.999
But this is changing.

00:04:26.000 --> 00:04:30.411
Climate change and decreases
in sea ice are also altering

00:04:30.412 --> 00:04:33.870
the underwater soundscape of the Arctic,

00:04:33.871 --> 00:04:38.091
which is a direct result
of human greenhouse gas emissions.

00:04:38.451 --> 00:04:41.251
We are, in effect, with climate change,

00:04:41.252 --> 00:04:45.370
conducting a completely
uncontrolled experiment with our planet.

00:04:45.710 --> 00:04:47.886
Over the past 30 years,

00:04:47.887 --> 00:04:51.692
areas of the Arctic have seen
decreases in seasonal sea ice

00:04:51.693 --> 00:04:56.561
from anywhere
from six weeks to four months.

00:04:56.562 --> 00:05:00.283
This decrease in sea ice
is sometimes referred to

00:05:00.284 --> 00:05:03.161
as an increase in the open water season,

00:05:03.162 --> 00:05:07.213
that is the time of year
when the Arctic is navigable to vessels.

00:05:07.313 --> 00:05:10.043
Not only is the extent of ice changing

00:05:10.843 --> 00:05:14.993
but the age and the width of ice is too.

00:05:15.303 --> 00:05:18.381
You may well have heard
that a decrease in seasonal sea ice

00:05:18.382 --> 00:05:22.172
is causing loss of habitat
for animals that rely on sea ice

00:05:22.173 --> 00:05:26.235
such as ice seals,
or walruses, or polar bears.

00:05:26.555 --> 00:05:31.333
Decreasing sea ice is also causing
increased erosion along coastal villages

00:05:31.334 --> 00:05:35.475
and changing prey availability
for marine birds and mammals.

00:05:35.925 --> 00:05:40.554
Climate change and decreases
in sea ice are also altering

00:05:40.555 --> 00:05:44.044
the underwater soundscape of the Arctic.

00:05:44.045 --> 00:05:46.185
What do I mean by soundscape?

00:05:46.635 --> 00:05:49.635
Those of us who eavesdrop
on the oceans for a living

00:05:49.636 --> 00:05:53.890
use instruments called hydrophones,
which are underwater microphones.

00:05:53.891 --> 00:05:57.896
We record ambient noise,
the noise all around us.

00:05:57.897 --> 00:06:01.176
The soundscape describes
the different contributors

00:06:01.177 --> 00:06:02.786
to this noise field.

00:06:02.787 --> 00:06:05.397
What we are hearing on our hydrophones

00:06:05.398 --> 00:06:09.257
are the very real sounds
of climate change.

00:06:09.467 --> 00:06:12.396
We are hearing these changes
from three fronts:

00:06:12.886 --> 00:06:17.598
from the air, from the water,
and from land.

00:06:18.108 --> 00:06:20.757
First: air.

00:06:20.758 --> 00:06:23.357
Wind on water creates waves.

00:06:23.358 --> 00:06:26.538
These waves make bubbles,
the bubbles break.

00:06:26.539 --> 00:06:29.468
When they do, they make noise,

00:06:29.469 --> 00:06:33.878
and this noise is like a hiss
or a static in the background.

00:06:33.879 --> 00:06:36.970
In the Arctic, when it's ice-covered,

00:06:36.971 --> 00:06:40.720
most of the noise from wind
doesn't make it into the water column

00:06:40.721 --> 00:06:45.550
because the ice acts as a buffer
between the atmosphere and the water.

00:06:45.551 --> 00:06:51.042
This is one of the reasons that the Arctic
can have very low ambient noise levels.

00:06:51.322 --> 00:06:54.051
But with decreases in seasonal sea ice,

00:06:54.052 --> 00:06:58.572
not only is the Arctic now open
to this wave noise

00:06:59.152 --> 00:07:01.912
but the number of storms
and the intensity of storms

00:07:01.913 --> 00:07:04.301
in the Arctic have been increasing.

00:07:04.302 --> 00:07:09.583
All of this is raising noise levels
in a previously quiet ocean.

00:07:10.273 --> 00:07:12.854
Second: water.

00:07:13.614 --> 00:07:18.662
With less seasonal sea ice,
sub-Arctic species are moving north

00:07:18.663 --> 00:07:23.346
and taking advantage of new habitat
that is created by more open water.

00:07:23.576 --> 00:07:28.415
Arctic whales, like this bowhead,
have no dorsal fin.

00:07:28.416 --> 00:07:33.166
because they have evolved
to live and swim in ice-covered waters.

00:07:33.167 --> 00:07:35.384
Having something sticking off of your back

00:07:35.385 --> 00:07:38.385
is not very conducive
to migrating through ice,

00:07:38.386 --> 00:07:42.596
and may, in fact, be excluding
animals from the ice.

00:07:42.597 --> 00:07:46.596
But now, everywhere we've listened,
we're hearing the sounds

00:07:46.597 --> 00:07:50.006
of fin whales, humpback whales,
and killer whales,

00:07:50.007 --> 00:07:52.357
further and further north

00:07:52.358 --> 00:07:54.997
and later and later in the season.

00:07:54.998 --> 00:08:00.557
We are hearing, in essence, an invasion
of the Arctic by sub-Arctic species,

00:08:00.737 --> 00:08:02.968
and we don't know what this means.

00:08:02.969 --> 00:08:08.106
Will there be competition for food
between Arctic and sub-Arctic animals?

00:08:08.107 --> 00:08:13.631
Might these sub-Arctic species introduce
diseases or parasites into the Arctic?

00:08:13.971 --> 00:08:17.017
What are the new sounds
that they are producing

00:08:17.018 --> 00:08:19.728
doing to the soundscape underwater?

00:08:19.729 --> 00:08:21.809
Third: land.

00:08:21.810 --> 00:08:24.849
By land, I mean people.

00:08:25.239 --> 00:08:29.275
More open water means
increased human use of the Arctic.

00:08:29.835 --> 00:08:31.319
Just this past summer,

00:08:31.320 --> 00:08:35.349
a massive cruise ship made its way
through The Northwest Passage,

00:08:35.350 --> 00:08:39.119
the once mythical route
between Europe and the Pacific.

00:08:39.799 --> 00:08:45.698
Decreases in sea ice have allowed humans
to occupy the Arctic more often.

00:08:45.699 --> 00:08:50.249
It has allowed increases
in oil and gas exploration and extraction,

00:08:50.250 --> 00:08:52.849
the potential for commercial shipping,

00:08:52.850 --> 00:08:54.901
as well as increased tourism.

00:08:56.001 --> 00:09:00.930
We now know that ship noise increases
levels of stress hormones in whales

00:09:00.931 --> 00:09:03.250
and can disrupt feeding behavior.

00:09:03.670 --> 00:09:05.374
Air guns, which produce

00:09:05.375 --> 00:09:10.834
loud, low-frequency 'whoomps'
every 10 - 20 seconds,

00:09:11.482 --> 00:09:14.982
change the swimming
and vocal behavior of whales.

00:09:15.322 --> 00:09:20.050
All of these sound sources
are decreasing the acoustic space

00:09:20.051 --> 00:09:23.563
over which Arctic marine mammals
can communicate.

00:09:24.293 --> 00:09:29.022
Arctic marine mammals
are used to very high levels of noise

00:09:29.023 --> 00:09:30.832
at certain times of the year,

00:09:30.833 --> 00:09:34.741
but this is primarily
from other animals or from sea ice.

00:09:34.742 --> 00:09:37.372
These are the sounds
with which they've evolved,

00:09:37.373 --> 00:09:40.656
and these are sounds
that are vital to their very survival.

00:09:41.116 --> 00:09:44.495
These new sounds are loud,
and they are alien.

00:09:44.815 --> 00:09:49.375
They might impact the environment
in ways that we think we understand,

00:09:49.945 --> 00:09:52.452
but also in ways that we don't.

00:09:52.662 --> 00:09:57.284
Remember, sound is the most
important sense for these animals;

00:09:57.285 --> 00:10:01.726
and not only is the physical habitat
of the Arctic changing rapidly

00:10:01.966 --> 00:10:04.715
but the acoustic habitat is, too.

00:10:04.716 --> 00:10:08.348
It's as if we plucked these animals up
from the quiet countryside

00:10:08.349 --> 00:10:12.076
and dropped them into a big city
in the middle of rush hour.

00:10:12.077 --> 00:10:14.056
They can't escape it.

00:10:14.057 --> 00:10:16.387
So what can we do now?

00:10:17.027 --> 00:10:19.679
We can't decrease wind speeds

00:10:19.680 --> 00:10:22.850
or keep sub-Arctic animals
from migrating north,

00:10:22.851 --> 00:10:28.582
but we can work on local solutions
to reducing human-caused underwater noise.

00:10:29.052 --> 00:10:32.399
One of these solutions
is to slow down ships

00:10:32.400 --> 00:10:34.218
that traverse the Arctic,

00:10:34.219 --> 00:10:38.143
because a slower ship is a quieter ship.

00:10:38.144 --> 00:10:41.882
We can restrict access
in seasons and regions

00:10:41.883 --> 00:10:46.710
that are important for mating,
or feeding, or migrating.

00:10:46.950 --> 00:10:50.159
We can get smarter about quieting ships

00:10:50.160 --> 00:10:53.520
and find better ways
to explore the ocean bottom.

00:10:54.120 --> 00:10:58.750
The good news is there are people
working on this right now.

00:10:58.751 --> 00:11:03.071
But ultimately, we humans
have to do the hard work

00:11:03.072 --> 00:11:05.952
of reversing, or at the very least,

00:11:05.953 --> 00:11:09.954
decelerating human-caused
atmospheric changes.

00:11:09.955 --> 00:11:14.954
So let's return to this idea
of a silent world underwater.

00:11:15.384 --> 00:11:17.114
It's entirely possible

00:11:17.115 --> 00:11:20.413
that many of the whales
swimming in the Arctic today,

00:11:20.414 --> 00:11:23.958
especially long-lived species
like the bowhead whale

00:11:23.959 --> 00:11:27.710
- that the Inuit say
can live two human lives -

00:11:27.735 --> 00:11:31.414
it's possible that these whales
were alive in 1956

00:11:31.415 --> 00:11:34.006
when Jacques Cousteau made his film.

00:11:34.446 --> 00:11:40.535
In retrospect, considering all the noise
we are creating in the oceans today,

00:11:41.015 --> 00:11:44.227
perhaps it really was "The silent world."

00:11:44.977 --> 00:11:46.385
Thank you.

00:11:46.386 --> 00:11:48.026
(Applause)