- It was just a fireball
and traveled so fast.
- I just saw flames all up
on the hill behind my house.
- It was Armageddon I'll tell you,
the fire coming in and
burning all around us,
- [Narrator] Alaska,
Arizona, California, Montana,
Oregon, Australia, Brazil,
Canada, Greece, Russia.
These are just some of the places
where in recent years, wildfires
have raged out of control.
NASA satellites detect
more than a million large
fires worldwide every year.
- The Western United States, for example,
has seen larger fires in each
of the last several years
and more intense burning,
and many times as fire spread faster,
making them more difficult
to put out and more dangerous
for the communities who
live in that vicinity.
- [Narrator] In many
cases, the blazes are set
by human activity,
but sometimes policy fuels the flames too.
Consider California,
the state's forests are overgrown in part
because of past federal policies
of putting out wildfires
rather than letting them burn.
Some of these policies were enacted
in response to a devastating fire in 1910,
in which millions of acres
burned more than 80 people died,
years passed and suppression
became the go to strategy
for dealing with fire.
- [Narrator] Ignition,
It only takes a minute
to wipe out a century.
- [Narrator] initiatives like
Smokey Bear urged Americans
to help prevent forest fires.
- Only you can prevent forest fires.
- In 1974, Congress passed
the Federal Fire
Prevention and Control Act
in an effort to save lives,
and that plan worked.
Around that time
according to the act fires
of all types killed more
than 12,000 people each year.
Today according to the
U.S Fire Administration,
the death toll is lower,
but-
- Part of the reason
we see increasing fuels
and increasing extreme fire behavior
is that we have a legacy
of putting fires out
and allowing fuels to
grow permitting fires
when they do start to get out of control,
- [Narrator] Overgrown
forests have an abundance
of small and medium trees
known as ladder fuels,
which can make fires more dangerous.
- Ladder fuels would allow
a surface fire burning
often slowly along the ground
to transition into the canopy,
or it can spread more rapidly.
And when those trees are burning,
the embers that are blown
by the wind can ignite
the neighboring trees,
they can also be spread further downwind.
- [Narrator] That's part of the story
of California's 2018 fire season.
The deadly campfire
was fed by dry weather,
fast winds and ladder fuels.
According to recent research,
20 million acres of forest land,
or nearly 20% of California would benefit
from what's known as fuel treatments.
Land managers can limit the
fuels that could create large,
fast moving fires in several ways,
including getting out vegetation,
think logging or clearing brush,
prescribed burns where small
fires are set deliberately,
or letting natural wildfires
in unpopulated areas
run their course under
the watch of local firefighters.
But clearing out brush can be expensive
and labor-intensive.
First since many of these
trees are small in diameter,
so they don't have
commercial value as timber
and there's little financial
incentive to remove them.
And federal policies
have historically favored
putting out fires as soon as
they start to keep people safe.
- Maintaining that balance
of different ecosystem types
IN different fire
frequencies is more difficult
when we move into areas with
more dense human populations.
And so the wild land
urban interface is really
where these two challenges meet,
where people are living in
communities against landscapes
that historically have had fire activity.
Those are landscapes that
are very difficult to protect
when fires do start.
- [Narrator] One of the factors affecting
California's wildfire season
is new housing construction
in fire prone areas.
Climate change is adding
to the problem too.
- Where fuels are abundant today
and where climate change is
leading to warmer and drier conditions,
we are already seeing more
extreme fire behavior.
- [Narrator] According
to recent Federal Data,
the last decade was the warmest on record.
During the summer of 2020
fires burned in the Arctic,
as parts of Siberia broke the record
for the highest temperature
ever recorded above
the Arctic circle.
- They're almost always too
cold and too wet to burn.
So as those landscapes,
which are warming three
times faster than the rest
of the planet, continue to warm and dry,
we certainly expect to see more fires
in those remote landscapes
directly in response
to climate change.
- [Narrator] In August of 2020, wildfires
most of them sparked by
lightning raged out of control
across California.
Earlier in the year,
state officials had warned
of high fire danger caused
by a dry winter and warm spring.
It's a pattern scientist
generally attribute
to climate change.
In May, the mountain
snowpack in California,
Sierra Nevada was just 13% of
normal and it's not just 2020,
half of California's 20
most destructive wildfires
have happened since 2015.
Across the forests of Southeast Australia,
NASA mapped more fires
between 2019 and 2020
than they had in the last 16 years.
The fires were fueled by
extreme heat and drought,
hotter, drier weather sucks
moisture out of the trees,
grasses, and other fuels
making them more flammable.
And this is making fire management
all the more complicated.
- So as conditions that
allow wildfires to spread
are lasting longer across the
United States and elsewhere,
there's a shorter and shorter window
where active management
could happen under conditions
that wouldn't risk fires
escaping and spreading
into lands as a wildfire.
- [Narrator] That means
fighting fire with fire
might not be an option for
certain regions anymore.
So to help with wildfires,
researchers are working on algorithms
to improve forecasting.
- [Doug] If we can
anticipate the timescales
and the locations where
fires are most likely,
we have the best chance
of trying to mobilize
and prepare resources to anticipate fires
and make up more timely
decision about which fires
to put out and which to let burn.
(soft music)
