(chanting in Hawa iian) - Pelehonuamea.

She is she who creates and destroys.

She is the volcano goddess.

She's a living force on this landscape.

- Kīlauea is one of the most active volcanoes on Earth.

- It's a puzzling, complicated system that only makes itself more complicated by how active it is.

- Without volcanoes, we wouldn't have Hawaii.

Volcanoes are the foundation of our islands.

- [Narrator] For the last 40 years, Kīlauea has been in a state of near constant eruption, providing researchers with a uniquely reliable setting to study one of our planet's most unpredictable and destructive forces.

In a time of climate panic, and tangible ecological destruction.

What can we learn about the survival of our planet from one of the harshest environments on Earth?

(gentle music) - [Stacey] So Hawaii Volcanoes National Park is 350,000 acres, which stretches from the coast all the way up to 14,000 feet at the summit of Mouna Loa.

- [Ku'ulei] We are in the Kīlauea area, and Kīlauea means "to spew lava."

And so even if you've never been here, but you understand that's what the name means, you know what to expect.

- [Patricia] Kīlauea is a little bit different from sort of the stereotypical pointy cone volcano because it's called a shield volcano.

Shield volcanoes form when lava is extra runny and can go really far from the vent where it comes out.

Right now, it's not erupting, but from 1983 to 2018, that was 35 years of near continuous eruption.

And then in 2018, we had a huge eruption, and we had what's called caldera collapse.

The summit of Kīlauea, in chunks, sort of, collapsed in on itself and dropped down about 500 meters, which is about as tall as the Empire State Building.

- [Ashton] In 2018, large, large sections of this road actually fell into the caldera.

The fact that it just one day decided to open up and swallow a huge section of road.

And then the parts that are still remain, thrown around like, just like little tinker toys.

Talk about kind of the awe-inspiring force that the volcano has.

- Now that we're in 2023, we've had three eruptions in one year so far.

And now we're waiting for the next one.

Volcanic gases are one of the main reasons we have volcanic eruptions in the first place.

So if you think about a bottle of soda and those explosions that you get, if you shake it up too much, those are all driven by those gas bubbles dissolved in the soda.

Eruptions are driven by gas bubbles dissolved in magma.

We measure sulfur dioxide and carbon dioxide.

And mostly the sulfur dioxide comes out during eruptions, but the carbon dioxide comes out before eruptions.

So if we can track that, that can help give us clues about whether or not the volcano's refilling with magma.

We want to make sure we're watching the gases and all of the other data all over the volcano, because it's not just the summit that's active.

Working on an active volcano like Kīlauea and always monitoring it is almost like being a doctor because the land here really does seem almost alive.

- If you thought about a volcano as a living, breathing entity and body, gravity is the body mass index.

So I use gravity meters, or gravimeters, to study variations in the acceleration of gravity, or the force of gravity that are measurable on the surface, but that are being caused by changes in the volcanic system.

And gravimetry is the only way to extract that data.

It's the only way we have of measuring changes in mass.

That first one was 16.

That's pretty good.

That's pretty stable.

These instruments can measure one one-billionth, of the force of gravity that we feel every day.

So unbelievably precise.

And can I use that as a precursory signal for warning?

Can I say, "Hey look, we saw a great change in gravity right now," and then 20 minutes later, the volcano erupted.

It's still cutting edge.

So the question is, I still don't know.

But we're trying.

The idea is to get to a measurement that is solely unique and is something that tells us about how much actual magma is moving into, or out of the system.

(chanting in Hawaiian) - The chants are hundreds and thousands of years of empirical data.

Our ancestors saw an eruption and they noted how the ground opens up.

They noted how the flow came, if it was a fast moving flow, and a slow moving flow.

And we've been fortunate lately to have a partnership with Hawaii Volcanoes National Park and Hawaii Observatories because I think we're telling the same story.

We're telling it through chant and narrative, and they're telling it through their scientific record.

For a long time, our language and our culture was seen as just fable.

And now that we show that our chants and our stories are not just cute little fairytales, there's value in it, there's lessons in it that we can extract from all of those chants and stories.

- To start to try to understand how a native Hawaiian forest is constructed over time, that's something that you can find only here at Hawaii Volcanoes National Park.

I was born and raised on this island, about 40 miles away from the park, and I always felt like working in Hawaii was much more meaningful and making a difference in this landscape that is super special.

This is Nahuku lava tube.

It was formed about 550 years ago by a river of lava.

The top part of the lava flow cooled, but the river of lava continued to flow underneath it.

The ōhiʻa are actually reaching their roots down through the little cracks in the roof of the lava tube, and eventually they'll widen those cracks out.

They're breaking down the rock into soil.

Eventually they'll transform this lava tube into a forest floor.

On an active volcanic landscape there's cycles of destruction, and then there's rebirth following that.

The ōhiʻa is the catalyst for the rebirth of the forest.

Ōhi'a trees are adapted to disperse across the landscape, find little tiny cracks and crevices in the rocks.

Ōhi'a trees will actually hold their breath when sulfuric acid is in the air to protect themselves.

- Not only is it the first pioneer plant on lava beds, it helps to break down this rock, but it collects water for our islands and gives us fresh water or spring waters.

That's the importance of ōhiʻa to us.

(gentle music) - [Patricia] We're always gonna live with volcanoes, whether it's here in Hawaii or the Pacific Northwest, like Mount St. Helens, Japan, Indonesia, New Zealand.

We have to understand them to better live with them.

And using that information for forecasting eruption and hazard mitigation.

- [Ashton] Kīlauea is anywhere from 200 to 300,000 years old.

And that's actually pretty young, geologically speaking.

We're about as old as Kīlauea, as a species.

And while we have this long history of observation here, we've just kind of scratched the surface of what we've observed, both scientifically, but then also, kind of culturally.

The most potential for discovery are in the most inhospitable environments.

Because those are the places that are the hardest to study.

- [Stacey] To be in this place where Pele is very present and alive, to be here is a privilege.

You're always subject to the whims of the volcano.

You never know when she's gonna decide to totally change the landscape on you.

This isn't the end of the story.

It's an ongoing story with Pele and her dance on the landscape.

(dramatic music) (gentle music) (gentle music continues)