Extreme temperatures and more severe droughts, the
result of human-caused climate change, have created a world that’s ready to
burn.
By Veronica
Penney
Sept. 16,
2020
https://www.nytimes.com/2020/09/16/climate/wildfires-globally.html
Wildfires
are devastating the American West, but the United States isn’t the only place
on Earth that’s burning. This year, other countries have also experienced their
worst wildfires in decades, if not all of recorded history.
In each
case, the contributing factors are different, but an underlying theme runs
through the story: Hotter, drier seasons, driven by the burning of fossil
fuels, have made the world more prone to erupt in flames.
“We don’t
have a fire problem; we have many fire problems,” said Stephen J. Pyne, an
emeritus professor at Arizona State University who studies wildfires and their
history. “One, obviously, is a deep one. It has to do with fossil fuels and
climate.”
Here’s a
look at some of the worst recent blazes and how humans played a role in them.
The Arctic
and Siberia
The Arctic
as a whole is experiencing warming at more than twice the pace of the rest of
the world. Record-low snow cover, high temperatures and dry soils, almost
certainly a result of human-caused climate change, have all contributed to the
fires.
This
summer, portions of the Arctic shattered wildfire records set just last year,
which at the time was the worst fire season in 60 years. The Russian town of
Verkhoyansk became the first place above the Arctic Circle to experience
temperatures over 100 degrees Fahrenheit, or about 38 Celsius, in June. Record
heat also thawed combustible, but usually frozen, peatland, which fed wildfires
that burned an area roughly the size of Belgium.
While no
lives were lost, smoke smothered the Russian countryside and the burned land
emitted a surge of planet-warming carbon dioxide — about as much as Norway
emits annually.
Indonesia
In the
humid tropics, climatic conditions play a smaller role in wildfires. There,
clearing and burning land for agriculture is the primary cause of fires.
In July,
Central Kalimantan Province on Borneo declared a state of emergency as fires
burned out of control. That followed severe fires in Indonesia last year and in
2015, the year of a drought in the country that was linked to El Niño, the
periodic warming of the tropical Pacific Ocean that can affect weather
worldwide.
Even
without dry conditions, though, agricultural practices played a crucial role in
the fires.
“It’s very,
very rare to see fires naturally,” said Ruth DeFries, a professor of
sustainable development at Columbia University. “When we see fires in the humid
tropics, there is a human ignition source behind it.”
“Without
the land use, you could have dry conditions associated with El Niño and not
have fires,” Dr. DeFries said.
Brazil
The worst
fires on record are burning now in the Pantanal wetlands in the country’s
south. Farther north, in the Amazon rain forest, tens of thousands of fires are
still burning after a summer of blazes. In June, Brazilian officials called the
Amazon fires the worst in 13 years.
As in
Indonesia, deforestation for agriculture is a primary culprit. Farmers and
ranchers cut down trees on the edge of the rainforest and set them on fire to
clear the land for crops or grazing. But climate change is a force multiplier:
During droughts like the current one in the country, those fires penetrate
farther into forests, burning more trees and causing more damage
Unlike the
wildfires in California, which burn tree canopies, fires in the Amazon often
creep along the forest floor “essentially no higher than my knee,” said
Jennifer Balch, an associate professor of geography at the University of
Colorado Boulder and director of the university’s Earth Lab. “And they can go
for a very long period of time.”
Argentina
Fires are
raging now across grasslands in the Paraná Delta and around farmland in central
Argentina, where farmers and ranchers have been burning fields for a century to
improve their soil. This year, the fires got out of control.
“It’s easy
for fires to leave the perimeters of someone’s property and just burn huge
areas,” said Virginia Iglesias, a research scientist at the Earth Lab at the
University of Colorado Boulder who lived in Argentina most of her life.
“It’s the
end of winter, and it’s been a really, really dry winter,” Dr. Iglesias said.
“These exceptionally dry conditions in central Argentina, and in many other
areas of the country, create conditions that are perfect for fires once you
have fuel.”
At the
beginning of this year, Australia was just emerging from its worst wildfire
season on record. Thousands of homes were lost and millions of acres burned. At
least 30 people died. Estimates of the number of animals killed range between a
few hundred million and a billion.
Researchers
found that human-caused climate change played a significant role in the fires,
making the high-risk conditions that led to widespread burning at least 30
percent more likely than in a world without global warming.
Now, as the
Southern Hemisphere heads into spring, Australians are bracing themselves for a
new season of blazes. Officials say they doubt this year’s fires will be as
severe, because there is simply not much left to burn, but homeowners are still
hastening to clear shrubs and weeds, and complete prescribed burns.
In the
short term, Dr. Pyne said, we can mitigate fire risks by designing more
fire-safe communities, creating better evacuation plans and improving fire
management on wild lands.
“Prescribed
fire is clearly going to be a part of that,” he said. “If you think of fire as
a contagion, which in many ways it is, prescribed burning is part of herd
immunity.”
When it
comes to human causes of climate change, “We need to take action, but that will
take a long time,” Dr. Pyne said. “We are going to be living with an enhanced
fire world for decades, at least.”
Veronica
Penney is a reporter covering climate change and a member of the 2020 Times
Fellowship class. @veronica_penney
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