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Wildfires -- sometimes called bushfires -- are uncontrolled fires
that burn through vegetation in areas like forests and grasslands.
And they're a perfectly natural part of many ecosystems.
Many forests actually need wildfires to survive -- they add
important nutrients back into the soil, and they can be required
for seed germination and growth.
Unfortunately, thanks to climate change, land use, and other factors,
many regions are experiencing longer, more dangerous wildfire seasons,
with longer-lasting, more frequent blazes.
So researchers are working hard to fight wildfires,
both as they rage and before they start, with the power of technology.
Here are four super high-tech ways we're trying to stop wildfires
in their tracks.
And one that's... a bit simpler.
One way tech can help us tackle wildfires is by improving
existing firefighting technologies.
In the case of chemical flame retardants, that means
making them... stickier.
Right now, firefighters use more than 100 million gallons
of chemical flame retardants—like ammonium polyphosphate,
or APP—to extinguish out-of-control blazes each year.
Firefighters apply APP to vegetation that's in the way of
an advancing wildfire, often by dropping it out of
specially-equipped planes.
The APP adheres to plants and creates a protective chemical coating.
As the APP burns, it releases water vapor, which helps
extinguish the flames.
It also leaves behind a black, fire-resistant charcoal residue
that protects the vegetation from burning.
So while it might look like a fire has burned APP-treated plants
to a crisp, it actually hasn't.
The goal of APP is to prevent wildfires from consuming the fuel
they need to keep growing… because when there's no more fuel,
there's no more fire.
So if APP can put out a wildfire, what's the big problem?
Well, while it does work, it's most effective at minimizing
the damage from fires that have already broken out.
That's because APP is water soluble and can be washed off
of plants easily.
High winds can blow it off, too.
So while APP is a great tool for fighting fires, it's not realistic
to use it for season-long fire prevention.
But scientists are working to change that by combining APP
with viscoelastic fluids.
A viscoelastic fluid is unique because it can behave both
like an elastic solid and a viscous liquid.
In other words, a viscoelastic fluid is both stretchy and sticky,
kind of like bread dough.
In a 2019 study, scientists at Stanford University announced
that they had developed a type of viscoelastic fluid that
combines plant-derived cellulose with colloidal silica particles.
The result is what its inventors have dubbed “molecular velcro,”
thanks to its ability to stick to plants way better than APP alone.
When you mix this viscoelastic fluid with APP, 50% more
fire retardant sticks to vegetation, and it can stay put
even after a half inch of rainfall.
In fact, in the researchers' tests, grass treated with this
mixture just… wouldn't catch on fire.
And even better: they think it's environmentally safe enough
to leave on plants long-term.
They hope this new viscoelastic fluid will one day
let firefighters protect vulnerable areas -- like steep inclines,
roadways, and man-made structures -- before wildfires ever break out.
Next up… drones!
Drones are the poster child for flashy tech.
And they're helping fight fires too -- in more ways
than you might expect.
Because drones are remotely operated, they're able to fly
into dangerous areas where it's not safe for people
or even aircraft to travel.
But scientists are also developing drones that can
fight fire with fire… literally.
Lighting a fire to fight a fire is called a backfire.
To do that, firefighters first create a containment line
in front of a wildfire to keep it from moving past a certain point.
Containment lines can be a naturally occurring barrier,
like a river. Often, though, they're artificial trenches.
Then, you have to light the backfire.
Which is where the flashy tech comes in.
Drones equipped with a system called IGNIS can swoop in
and set a new fire on the wildfire side of the containment line.
The backfire consumes fuel that is in the path of the
original wildfire, and because fires need fuel to burn,
the backfire prevents the wildfire from spreading.
The IGNIS-equipped drones light backfires by dropping spheres
the size of ping pong balls, called Dragon Egg spheres,
wherever firefighters want the new fires to start.
The Dragon Eggs are injected with a chemical called glycol
right before they're released from the drone, which causes
a chemical reaction that ignites 30 seconds after
the Dragon Egg is released.
That ensures that the Dragon Eggs catch fire after they've
reached the ground.
The IGNIS system typically carries around 400 Dragon Egg spheres,
and it can drop them at a rate of up to 120 spheres per minute.
That lets one IGNIS-equipped drone ignite several hundred hectares
of land every hour, which helps firefighters start a backfire
quickly and safely.
These fire-starting drones can also set controlled burns,
which firefighters and foresters use to safely remove
accumulated leaves, limbs, grass, and debris that
can fuel dangerous wildfires.
And, drones can even help restore burned areas.
Drones fitted with seed distribution systems can help
reseed deforested areas far away from people, which can help
forests recover from fires faster.
Researchers have developed drones that are specifically designed
to help replant wildfire-ravaged areas quickly and efficiently.
First, one set of drones creates a 3D map of an area,
and once that's done, the seeding drones get to work.
Each drone can carry about 26 kilograms of seed vessels,
which are small cubes containing a mixture of soil,
fertilizer, and tree seeds.
The drones then drop the seed vessels over the fire-ravaged area.
Right now, each drone can plant about one third of a hectare
each flight, and a full swarm of five drones can plant
about 16 hectares a day.
That means a single drone swarm could replant an area
the size of New York's Central Park in just three weeks.
So, sorry, Johnny Appleseed… it looks like you might have been replaced.
Artificial intelligence is also adding some seriously
high-tech juice to our wildfire-prevention kit.
For instance, in a 2017 paper, one group of scientists proposed
an AI technology, called Particle Swarm Optimized Neural Fuzzy,
or PSO-NF.
Now, while that name might tell computer scientists everything
they need to know, for the rest of us, that basically means
that the AI calculates an environment's susceptibility to wildfires --
specifically, a tropical forest.
It does this by taking important environmental data points
like land use, elevation, temperature, rainfall, and wind speed.
Then, it builds a Geographic Information System, or GIS, database.
A GIS database compiles, stores, and analyzes all sorts of
geographical data, like surface elevation, vegetation types
and densities, and even the location of man-made structures
like buildings and streets.
Once researchers build a GIS database of a specific area,
the PSO-NF AI can then analyze the data and look for patterns,
which allow it to predict when and where wildfires could break out.
A tech company in California is developing AI technology
that detects wildfires as soon as they start.
To do this, an AI program analyzes satellite images
to monitor fire-prone areas.
The AI searches for wildfire signs that are invisible
to the naked eye, like temperature spikes, smoke, or hotspots.
Once the AI spots the warning signs of a fire, it alerts
the authorities so they can respond before the blaze
grows out of control.
Eventually, this technology will be able to scan California's
33 million acres of forest every 10 minutes as a first line
of defense against potentially devastating wildfires.
So AI can help us predict wildfires and spot them
as soon as they start -- or even before.
But what about when they're already burning out of control?
Another group of scientists at the University of California
San Diego have developed an AI technology called Firemap
that's helping firefighters predict the path of a wildfire
in real time.
Firemap uses satellite imaging to get a better understanding
of the development, terrain, and even vegetation of an area,
which it uses to calculate how a fire might move
through that specific location.
It also connects to hundreds of remote weather stations
so it can include pertinent weather data, like wind speed
and wind direction, into its calculations.
The program then uses the data to create a model that can predict
the movement of an active blaze.
That way, firefighters can deploy emergency workers and supplies
to where they're needed most.
But even with all of these remote technologies,
fighting wildfires still requires sending lots of people
into pretty dangerous situations.
The unpredictability of wildfires makes them especially dangerous
for firefighters, since conditions can go from safe to deadly
within minutes.
But we might be able to help them do their jobs
and stay safe through the use of augmented reality.
Being able to see through smoke, for example,
would be a huge deal.
A new augmented reality technology called C-Thru gives
firefighters a heads-up display inside their facemasks.
The C-Thru system uses a thermal camera to map the terrain
in front of a firefighter in real time, even
in the smokiest conditions.
An on-board computer then turns the data into outlines
of the surrounding area and anybody within it, which is then sent
to the mask's display.
So even if it's dark, smokey, or both, they can hopefully see
well enough to make it back to safety.
This AR technology is actually being developed for structural fires,
like burning buildings, but it's being adapted
for fighting wildfires, too.
But not all solutions have to be high-tech --
sometimes going old-school is best.
And this one's really old school.
It's the small but mighty... goat.
One of the best ways to prevent wildfires from getting out of control
is to limit the amount of fuel the fires have --
stuff like fallen leaves, grasses, and other underbrush.
But it can be hard for humans to clear out vegetation
in areas with rough terrain or steep inclines.
That's why some states have turned to goats to keep wildfire fuel
to a minimum.
Goats are tiny, efficient mulchers that can chew through
underbrush in places that weed whackers and mowers can't reach.
In fact, one goat can eat up to four and a half pounds of vegetation
a day… making them fuzzy, adorable vegetation decimators.
And as an added bonus, the goats leave behind
some pretty great fertilizer too.
So while goats can't fly over wildfires or predict where one
will crop up next, they can provide an eco-friendly, low-cost,
highly cute option for keeping wildfire-feeding
vegetation under control.
Unfortunately, many of these technologies are still in development
and not ready for widespread use.
And even if they were widely available, they don't address
the real underlying causes of wildfires: things like
climate change and poor land management.
But until we can bring those structural issues under control,
we'll at least have help from fire-starting drones and hungry goats.
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