- Currently, the state-of-the-art
in tornado detection is eyesight,
and the weather services train up what they call spotters,
who if they see a funnel hits the ground,
they get on their phone and call it in.
- Twisters are incredibly dangerous forces of nature,
and they can barrel into towns with little-to-no warning.
And unreliable predictions
can often cause alarms to be ignored.
But at the National Center of Acoustics,
a team of audio specialists are searching for a faster,
more reliable, and safer way to warn people
in tornado-heavy areas.
And the solution isn't what you'd expect.
- This is the type of sensor that was designed
primarily for the Nuclear Weapon Test Ban Treaty.
(explosions)
This is Just Might Work,
a show about surprising solutions to our biggest problems.
Every year in the United States, tornadoes cause about
$400 million in damage and kill around 70 people.
Despite their destructive force,
the people in their path typically receive
only about a 10-minute warning.
This is all in part because tornado prediction
is really unreliable.
Currently, meteorologists are only able to use radar
to identify the kinds of conditions
that tornadoes might exist in.
- They can pick out hotspots
that might be tornadoes, but that's not
what they depend on for actual detection.
- 7 out of 10
tornado warnings are false alarms.
This means that people who live in Tornado Alley
are used to hearing and even ignoring a lot of sirens.
(loud sirens)
To make things even more unpredictable,
experts speculate that changes in the climate
are actually shifting the boundaries
of Tornado Alley into new areas of the country.
All these forces at play are making the need for a better
tornado warning system, more and more urgent.
- Alright, how's my hair,
is it still gray?
- Roger Waxler is not a meteorologist.
- We don't have meteorologists in this group,
we're, at best, amateurs when it comes to meteorology.
My background is in Quantum Field Theory,
and our specialty in our group is
really just detection and phenomenology
of infrasound propagation in the atmosphere.
(record skipping)
I tend to overexplain, so stop me if I'm doing such.
- In simpler terms, Waxler and his team
study acoustics, and they can listen
to all sorts of things the human ear can't.
- That's right, that's better.
Elephants communicate in infrasonic band, actually.
Volcanoes produce infrasound when they're active.
The Aurora Borealis produces an infrasound signal;
meteors that explode in the atmosphere.
Lightning.
- But Waxler's team wasn't pulled together
to listen to any of those things.
They came together to listen for nuclear bombs.
(bomb explodes)
- In the 1990s, more than 30 countries
signed on to the
Comprehensive Nuclear Test Ban Treaty,
meant to put a halt to any sort of testing on nuclear bombs.
And they commissioned these sensor rays
to listen for the infrasonic signatures of nukes.
- The explosion that the Israelis set off
was detected infrasonically as far away as Mongolia,
which is about 6,000 kilometers away.
This was validation of the sensor technology.
This is one of the sensors that we make in-house.
We have it underneath this dome
to protect from wind noise.
And this is the type of sensor that was designed primarily
for the Nuclear Weapon Test Ban Treaty.
But then we found we can use it well for many other things.
So it was pointed out back in the ‘60s
that tornadoes emit infrasound.
We were skeptical, but we had the funding.
And so we dutifully went out and set out arrays
of microphones in Oklahoma and captured signals
from tornadoes that were spot on.
We realized the way to go is to put out arrays
and leave them in the region for the entire season.
- Ever since Waxler and his team
have been tracking tornadoes through acoustics,
they've never had a false alarm
or had a single twister slip under their radar.
- The very smallest tornadoes we've detected from
actually from 80 kilometers.
I don't think the size matters.
- As long as the winds, which is what all this is about,
are blowing in the right direction,
we can hear the tornado from 50 to 100 kilometers away,
in almost every case.
- This means that if we could place
these sensors across areas where tornadoes are prevalent,
we can know with certainty
when and where tornadoes form,
and issue advanced warnings,
all through a remote, always-on system.
For Roger and his team, the next step is to investigate
whether they can use sound to know if a tornado
is forming before it even touches down.
- It's a question in our minds,
whether we pick it up before it hits the ground or not.
If there was a signal produced when the vortex forms,
which we could pick up, that would be ideal.
- With so many false warnings,
lack of trust in those warnings,
and crude measurement of where tornadoes
are located at any given moment, the stakes
for finding a better tornado warning system are high.
And while it's uncertain how exactly changes in the climate
will affect tornado season, early research indicates
the tornadoes of the future might be less frequent,
but more powerful,
and that they can show up in new places.
- Tornadoes terrify this part of the world and people die.
What happened with us
was we were pursuing this technology
more or less by accident.
We have the expertise in infrasound detection.
We found it worked and realized that
we could potentially save lives.