0:00:01.440,0:00:04.040
I'm an underwater explorer,

0:00:05.480,0:00:08.280
more specifically a cave diver.

0:00:09.200,0:00:11.816
I wanted to be an astronaut[br]when I was a little kid,

0:00:11.840,0:00:16.440
but growing up in Canada as a young girl,[br]that wasn't really available to me.

0:00:17.680,0:00:21.456
But as it turns out,[br]we know a lot more about space

0:00:21.480,0:00:25.816
than we do about the underground waterways[br]coursing through our planet,

0:00:25.840,0:00:28.800
the very lifeblood of Mother Earth.

0:00:29.720,0:00:33.096
So I decided to do something[br]that was even more remarkable.

0:00:33.120,0:00:35.576
Instead of exploring outer space,

0:00:35.600,0:00:38.760
I wanted to explore[br]the wonders of inner space.

0:00:39.920,0:00:41.576
Now, a lot of people will tell you

0:00:41.600,0:00:45.720
that cave diving is perhaps[br]one of the most dangerous endeavors.

0:00:46.560,0:00:49.456
I mean, imagine yourself[br]here in this room,

0:00:49.480,0:00:52.376
if you were suddenly[br]plunged into blackness,

0:00:52.400,0:00:54.816
with your only job to find the exit,

0:00:54.840,0:00:57.176
sometimes swimming[br]through these large spaces,

0:00:57.200,0:01:00.536
and at other times[br]crawling beneath the seats,

0:01:00.560,0:01:03.096
following a thin guideline,

0:01:03.120,0:01:07.856
just waiting for the life support[br]to provide your very next breath.

0:01:07.880,0:01:09.600
Well, that's my workplace.

0:01:10.760,0:01:12.736
But what I want to teach you today

0:01:12.760,0:01:17.136
is that our world[br]is not one big solid rock.

0:01:17.160,0:01:19.120
It's a whole lot more like a sponge.

0:01:19.960,0:01:23.816
I can swim through a lot of the pores[br]in our earth's sponge,

0:01:23.840,0:01:25.256
but where I can't,

0:01:25.280,0:01:30.296
other life-forms and other materials[br]can make that journey without me.

0:01:30.320,0:01:33.336
And my voice is the one[br]that's going to teach you

0:01:33.360,0:01:36.280
about the inside of Mother Earth.

0:01:38.640,0:01:41.616
There was no guidebook available to me

0:01:41.640,0:01:47.696
when I decided to be the first person[br]to cave dive inside Antarctic icebergs.

0:01:47.720,0:01:52.136
In 2000, this was the largest[br]moving object on the planet.

0:01:52.160,0:01:54.176
It calved off the Ross Ice Shelf,

0:01:54.200,0:01:57.136
and we went down there[br]to explore ice edge ecology

0:01:57.160,0:01:59.800
and search for life-forms beneath the ice.

0:02:00.440,0:02:03.616
We use a technology called rebreathers.

0:02:03.640,0:02:07.856
It's an awful lot like the same technology[br]that is used for space walks.

0:02:07.880,0:02:10.336
This technology enables us to go deeper

0:02:10.360,0:02:13.096
than we could've imagined[br]even 10 years ago.

0:02:13.120,0:02:15.176
We use exotic gases,

0:02:15.200,0:02:20.400
and we can make missions[br]even up to 20 hours long underwater.

0:02:21.160,0:02:23.336
I work with biologists.

0:02:23.360,0:02:27.896
It turns out that caves[br]are repositories of amazing life-forms,

0:02:27.920,0:02:30.720
species that we never knew existed before.

0:02:31.760,0:02:35.056
Many of these life-forms[br]live in unusual ways.

0:02:35.080,0:02:39.016
They have no pigment[br]and no eyes in many cases,

0:02:39.040,0:02:43.536
and these animals[br]are also extremely long-lived.

0:02:43.560,0:02:47.016
In fact, animals swimming[br]in these caves today

0:02:47.040,0:02:49.536
are identical in the fossil record

0:02:49.560,0:02:52.896
that predates the extinction[br]of the dinosaurs.

0:02:52.920,0:02:56.656
So imagine that: these are[br]like little swimming dinosaurs.

0:02:56.680,0:03:00.120
What can they teach us[br]about evolution and survival?

0:03:01.120,0:03:05.136
When we look at an animal[br]like this remipede swimming in the jar,

0:03:05.160,0:03:08.016
he has giant fangs with venom.

0:03:08.040,0:03:12.296
He can actually attack something[br]40 times his size and kill it.

0:03:12.320,0:03:14.096
If he were the size of a cat,

0:03:14.120,0:03:16.720
he'd be the most dangerous[br]thing on our planet.

0:03:17.920,0:03:21.176
And these animals live[br]in remarkably beautiful places,

0:03:21.200,0:03:25.816
and in some cases,[br]caves like this, that are very young,

0:03:25.840,0:03:27.576
yet the animals are ancient.

0:03:27.600,0:03:28.880
How did they get there?

0:03:29.880,0:03:32.056
I also work with physicists,

0:03:32.080,0:03:35.696
and they're interested oftentimes[br]in global climate change.

0:03:35.720,0:03:38.016
They can take rocks within the caves,

0:03:38.040,0:03:41.096
and they can slice them[br]and look at the layers within with rocks,

0:03:41.120,0:03:43.056
much like the rings of a tree,

0:03:43.080,0:03:45.096
and they can count back in history

0:03:45.120,0:03:48.816
and learn about the climate on our planet[br]at very different times.

0:03:48.840,0:03:51.336
The red that you see in this photograph

0:03:51.360,0:03:54.696
is actually dust from the Sahara Desert.

0:03:54.720,0:03:58.816
So it's been picked up by wind,[br]blown across the Atlantic Ocean.

0:03:58.840,0:04:03.216
It's rained down in this case[br]on the island of Abaco in the Bahamas.

0:04:03.240,0:04:04.856
It soaks in through the ground

0:04:04.880,0:04:08.856
and deposits itself[br]in the rocks within these caves.

0:04:08.880,0:04:12.696
And when we look back in the layers[br]of these rocks, we can find times

0:04:12.720,0:04:15.496
when the climate[br]was very, very dry on earth,

0:04:15.520,0:04:19.279
and we can go back[br]many hundreds of thousands of years.

0:04:20.560,0:04:22.816
Paleoclimatologists are also interested

0:04:22.840,0:04:26.136
in where the sea level stands were[br]at other times on earth.

0:04:26.160,0:04:28.376
Here in Bermuda, my team and I embarked

0:04:28.400,0:04:31.456
on the deepest manned dives[br]ever conducted in the region,

0:04:31.480,0:04:33.096
and we were looking for places

0:04:33.120,0:04:36.656
where the sea level[br]used to lap up against the shoreline,

0:04:36.680,0:04:39.520
many hundreds of feet[br]below current levels.

0:04:40.880,0:04:44.376
I also get to work with paleontologists[br]and archaeologists.

0:04:44.400,0:04:48.776
In places like Mexico,[br]in the Bahamas, and even in Cuba,

0:04:48.800,0:04:53.496
we're looking at cultural remains[br]and also human remains in caves,

0:04:53.520,0:04:54.776
and they tell us a lot

0:04:54.800,0:04:57.880
about some of the earliest[br]inhabitants of these regions.

0:04:58.760,0:05:02.256
But my very favorite project of all[br]was over 15 years ago,

0:05:02.280,0:05:04.804
when I was a part of the team[br]that made the very first

0:05:04.828,0:05:08.136
accurate, three-dimensional map[br]of a subterranean surface.

0:05:08.160,0:05:10.536
This device that I'm[br]driving through the cave

0:05:10.560,0:05:15.016
was actually creating[br]a three-dimensional model as we drove it.

0:05:15.040,0:05:17.096
We also used ultra low frequency radio

0:05:17.120,0:05:21.800
to broadcast back to the surface[br]our exact position within the cave.

0:05:22.320,0:05:27.136
So I swam under houses and businesses[br]and bowling alleys and golf courses,

0:05:27.160,0:05:30.320
and even under a Sonny's BBQ Restaurant,

0:05:31.080,0:05:33.176
Pretty remarkable, and what that taught me

0:05:33.200,0:05:36.096
was that everything we do[br]on the surface of our earth

0:05:36.120,0:05:38.536
will be returned to us to drink.

0:05:38.560,0:05:43.336
Our water planet is not just[br]rivers, lakes and oceans,

0:05:43.360,0:05:48.136
but it's this vast network of groundwater[br]that knits us all together.

0:05:48.160,0:05:52.016
It's a shared resource[br]from which we all drink.

0:05:52.040,0:05:56.336
And when we can understand[br]our human connections with our groundwater

0:05:56.360,0:05:59.016
and all of our water resources[br]on this planet,

0:05:59.040,0:06:00.776
then we'll be working on the problem

0:06:00.800,0:06:04.160
that's probably the most important[br]issue of this century.

0:06:05.040,0:06:08.456
So I never got to be that astronaut[br]that I always wanted to be,

0:06:08.480,0:06:12.096
but this mapping device,[br]designed by Dr. Bill Stone, will be.

0:06:12.120,0:06:13.536
It's actually morphed.

0:06:13.560,0:06:16.856
It's now a self-swimming autonomous robot,

0:06:16.880,0:06:18.536
artificially intelligent,

0:06:18.560,0:06:22.136
and its ultimate goal[br]is to go to Jupiter's moon Europa

0:06:22.160,0:06:26.760
and explore oceans beneath[br]the frozen surface of that body.

0:06:27.480,0:06:29.400
And that's pretty amazing.

0:06:30.160,0:06:35.880
(Applause)