(bright music) - Whoa, there it is. - [Arlo] This is Mount
Erebus in Antarctica. - [Jessie] There is hot magma right pretty much beneath our feet. - [Caitlin] The southernmost
active volcano in the world. - [Jessie] So it's this pretty
hulking mass of a volcano. It just makes you get a
sense of how small you are in the grand scheme of things. - [Arlo] It's the most
extreme Antarctic Extreme. - [Caitlin] Mount Erebus
is located on Ross Island, just a few miles from the
largest research station in Antarctica, McMurdo Station. (upbeat music) - [Arlo] Almost everywhere we went, the volcano loomed over us. - [Caitlin] Ross Island
is a volcanic island made up of jagged rock,
treacherous glaciers, and cracks that can be hard to find. So, flying is the only
practical way to get there. - But that doesn't mean it's easy. We've been delayed over
and over and over again. - We've been here two weeks
trying to get this flight off. - [Arlo] Conditions have to be perfect to fly up to Mount Erebus because we do not want to get
stuck up there in bad weather. The remnants of what can happen
if we do are still visible. - [Caitlin] How high are we now? - [Pilot] We're at 12,000. - [Caitlin] Almost there. The volcano is 12 1/2 thousand feet high. So we use canisters of
oxygen to help us breathe. - [Arlo] When I open the
window to take photographs, my fingers go numb. Extreme cold at this altitude is no joke. - [Caitlin] At Erebus's summit is a crater billowing with gas, mostly
water vapor and carbon dioxide from the volcano. Did you see any bubbling lava? - No bubbling lava, a lot of vapor. - Sometimes you can spot
a bubbling lava lake. It's one of only eight
volcanoes in the world that has one. And this is one of the reasons
scientists want to come here. Today, we're landing on the flanks of the volcano with Jessie Crane, who's spent three seasons
studying the volcanic gases on Mount Erebus. Negative 30 degrees, oh my god. This is probably the coldest weather I've ever been in in my entire life. The first thing I notice when I get out of the
helicopter, my snot is freezing. - [Jessie] And so is your hair. - Oh gosh, is it gonna
like break off? (laughs) - [Arlo] When I got off the helicopter, the first thing I noticed was
that something wasn't right. I felt dizzy, I started
to have tunnel vision, and I was completely zoned out. - [Caitlin] At first, I thought
Arlo was just spellbound by the view or something. It took me a little while to realize he was actually suffering
from altitude sickness. - [Arlo] I couldn't
think, I was just dazed. - [Caitlin] And we're
not even at the summit where much of the science is done. - [Jessie] It's not so bad being up there, but you have to hike
another 2000 feet, uphill. - At altitude, yeah.
- At altitude, in the cold. So it can be pretty tough. - [Caitlin] Turns out,
getting to the crater rim can be treacherous for
another reason, too. - [Jessie] It actually has pretty regular Strombolian eruptions. That's where a volcano just
builds up some pressure on the inside and then it goes pop, and it blows a bunch of
lava out the top of it. - [Caitlin] Strombolian
eruptions get their name from the Stromboli volcano in Italy, which regularly has this type of eruption. They're relatively small eruptions, and release the pressure
from inside the volcano. But these small eruptions are
also what keeps McMurdo safe, since pressure is released in small spurts instead of big disasters. - [Jessie] It's not building
up a ton of pressure so it's not like Mount St. Helens. It's just off-gassing
a little bit at a time, and you can see from looking around that it has had eruptive periods that have lava flow associated with them. That's how the volcano was
built, one lava flow at a time. - [Caitlin] While the
most visible activity is at the crater, we're
actually standing right next to another scientific marvel. (gentle music) - [Jessie] Sort of like a
hollow, upside down icicle. These are fumaroles, we
call them ice towers. - [Caitlin] Fumaroles are
normal volcanic features. On most volcanoes, like
this one in Hawaii, they look just like steam
seeping out of the ground. - [Jessie] You get all
of that gas, water vapor, and carbon dioxide coming
up through the side of the volcano, but here,
when it hits the air, that steam freezes. - [Caitlin] These towers are fascinating because they're castles
for exotic bacteria that can survive in the dark, steamy, and nutrient-poor environment. It looks like something out of Dr. Seuss. - [Jessie] It does look like
something out of Dr. Suess. Yeah they're crazy, and every one of them sort of has its own personality. - [Arlo] It seems crazy
that anything can live here, in these high altitude
volcanic ice towers. But it also seems pretty weird
that in this land of ice, there's an active volcano. How did this volcano come to be? - [Jessie] We're sitting
on top of a large feature called the Terror Rift. And that's the source of the volcanism. That's why there's magma
coming up near the surface and feeding this volcano. - [Caitlin] There's actually a rift zone that runs across Western Antarctica. A rift is where a continent is stretching apart and thinning, which allows hot magma to
come close to the surface. That's why there's a volcano here that's emitting carbon dioxide. No matter how cold it gets
on the surface of Earth, the inside of the planet is still hot. And that's a really good thing because many scientists think
that hundreds of millions of years ago, the whole
world was covered in ice. But because volcanoes like this one continue to churn away under the ice, they finally put out enough CO2
to heat up the planet again. So this place isn't only spectacular to visit and study today, but it's also kind of like a
window into our planet's past. - [Arlo] And for me, this was a glimpse into just how extreme
the conditions can be for the scientists who come here. Fortunately, I recovered pretty quickly once I got back in the helicopter. (gentle music) - So we just got back from probably what was the most
amazing helicopter flight of either of our lives. - No no no.
- Our entire life. - Not the most exciting
helicopter ride of our lives. The most exciting moment of our lives! This is the greatest,
we've peaked, this is it. (ethereal music) (bright music)
