Wildfires will increase in intensity and number and spread to new areas, the United Nations has reported
The report’s authors characterized extreme wildfires as destructive fires that were once rare but are now happening more often, burning longer, hotter and more intensely. They spread quickly, often spiraling out of control, and even move into areas that should be waterlogged or frozen, such as bogs and permafrost.
“Fires change because we change the conditions under which fires occur,” he said.
Due to a combination of climate change and land use change, there has been a “dramatic shift” in wildfire patterns around the world. Some regions, such as the Arctic, are likely to experience a significant increase in fires by the year 2100. The tropical forests of Indonesia and the southern Amazon are also expected to experience an increase in fires if greenhouse gas emissions greenhouse effect are not controlled.
The report was spurred by a series of wildfire disasters in 2017 in Portugal, Canada and California – shocking events that reappeared in subsequent years in new locations, but often under similar conditions, such as extreme heat, drought, high winds and overgrown or poorly managed vegetation. landscapes.
Released as the United Nations Environment Assembly meets in Nairobi on February 28, the report calls for a step change in the way humans deal with wildfires, from an approach that emphasizes firefighting to an approach that seeks to prevent catastrophic fires, as communities learn to live with such blazes.
Extraordinary fires around the world
The vast majority of wildfires on the planet are mild and help the environment, but a small percentage have turned extreme, with devastating effects. “From Australia to Canada, from the United States to China, across Europe and the Amazon, wildfires are wreaking havoc on the environment, wildlife, human health and infrastructure,” says The report.
“We had to define wildfires for our purposes as those that are unusual or extraordinary and cause concern,” said Andrew Sullivan, a wildfire scientist at the Commonwealth Scientific Industrial Research Organization (CSIRO) in Canberra. , Australia, and a publisher and author. of the report. “We needed to come up with a definition that encompassed the full spectrum of potential wildfire behavior.”
This definition can include flames that shoot up from the canopy of trees or those that crawl through bogs but still emit a huge amount of carbon into the atmosphere.
The past five years have seen many wildfire episodes that were once considered rare or extreme scenarios:
- In 2017 and 2018, a series of wildfires in Portugal, Greece, California and British Columbia sounded the alarm and seemed to usher in a new era of wildfires. Deadly and destructive fires continued in 2020 in the Pacific Northwest and California, which had its worst fire season on record with 4 million acres burned. In 2021, extreme fires once again swept across western North America, destroying two rural towns and chewing through millions of acres of forest. All were associated with extreme heat, drought and/or dangerous fire weather.
- Australia’s 2019-20 fire season has seen extreme fires rage for many months. Fueled by record temperatures, severe drought and high winds, the fires encroached on populated areas during the continent’s ‘black summer’, killing 33 people, with nearly 500 additional deaths attributed to the effects of smoke on the health.
- In 2020, the world’s largest tropical wetland, the Pantanal in South America, burned following severe drought and scorching weather. Nearly a third of this biodiversity hotspot – which stretches across Brazil, Paraguay and Bolivia – has been lost, and likely many endangered species with it.
- Humid forest ecosystems in South America and other regions are experiencing unusual fire activity due to human activities such as logging, road building, agriculture, and mining. Loss of tree canopy in disturbed forests promotes the growth of fuels on the forest floor; exposed, they then dry out quickly and are vulnerable to the spread of fire. Recent studies have shown a staggering loss of trees and biodiversity following fires in rainforests.
- In 2020, wildfires in the Russian Arctic scorched tens of millions of hectares following spring and summer temperatures 4 to 6 degrees Celsius higher than normal. It was the latest in a string of large-scale blazes in recent years, in a region that is warming twice as fast as the rest of the planet. The burning of arctic peatlands threatens to turn a crucial carbon sink into a carbon source.
Studies have linked several recent wildfire episodes to climate change, including the 2017 wildfires in British Columbia, the 2019-2020 black summer in Australia, and the 2020 wildfires in the Arctic, as well as the extreme heat wave of 2021 that preceded wildfires in British Columbia and the Pacific Northwest. .
From firefighting to land stewardship
As fire behavior becomes more intense, firefighting becomes less effective and more dangerous. In the face of extreme weather conditions, this can be futile.
“We spend a huge amount of money on law enforcement, especially in the developed world,” said Peter Moore, report author and forestry officer at the UN Food and Agriculture Organization. “This solution has run its course – in my opinion, it has reached its limits.”
In addition to reducing greenhouse gas emissions, the most effective measures One way to reduce fire intensity and protect communities is to reduce the amount of vegetation and debris that can be burned, through prescribed burning, mechanical thinning, animal grazing and other practices.
A big part of the problem is that a sense of land stewardship was lost with the decline of family farming and indigenous knowledge, Moore said, as urban dwellers with little experience of land care moved into rural areas.
In Australia and North America, for example, past Indigenous practices like cultural burning “have been almost completely erased, but we can harness them in collaboration with Indigenous peoples,” he said. “How you recreate that kind of soft, persistent, cohesive interaction with the landscape – that’s what you need.”
Don Hankins, professor of geography at California State University, Chico, said indigenous peoples have never been allowed to practice burning on ancestral lands, although policies are starting to change after recent severe fire seasons in the western United States and around the world.
The authors hope the report will shed some light on the complexity of the problem – a problem that has solutions that work, but no silver bullet to get out of the current quagmire. They also hope that the United Nations Environment Program will serve as a clearinghouse for one country to learn from another’s wildfire experience.
“No country has yet formulated the perfect response, but many are making progress in different aspects of wildfire risk management,” the report said. “Together we can learn from each other.”