Only 16 fires produced in the last decade were responsible for 82% of the total area burned in Chile in half a century. In the southern summer of 2019 to 2020, 23 million hectares burned in Australia, an area equivalent to half of Spain. The 6,669 fires unleashed in Canada in 2023, whose ashes reached Galicia, made that year the worst in its history. Siberia has been suffering from large-scale fires for five summers. And the 10,518 fires produced in Spanish territory in 2022 destroyed 115,195 wooded hectares. For some, these signs indicate that the planet is entering a new age of fire, the Pyrocene. For others, the relationship between humans and fires has not changed all that much.
Fire is one more element of ecosystems, as are the species and the relationships between them that make it up. Its domain was, for many, the basis of human expansion. For millennia, humans have used it to manage their environment, opening clearings to cultivate or revitalize the soil after harvesting. But in recent decades, words and concepts have entered into circulation that indicate that something is changing: megafires, pyrocene, sixth generation fires… Although for scientists, they are somewhat confusing terms and subject to discussion, almost everything indicates that something it is changing. In a special published by scientific journals One Earth and Cell Reports Sustainability, dozens of fire ecologists and fire experts raise some of the elements that are leading in this new era of fire, such as the increase in available fuel or its flammability, which would explain the scale that many fires reach today and that were previously exceptional. .
“Globally, the increase in flammability is explained by several interrelated factors,” says Spanish professor and director of the Center of Excellence for Forest Fire Research at the Australian National University, Marta Yebra. “First, climate conditions are experiencing significant changes, characterized by reductions in precipitation and prolonged periods of drought in various parts of the world, from Canada to Australia,” she adds. This would be causing a decrease in the forest’s capacity to act as its own firefighter, by reducing its environmental humidity. For Yebra, such changes would be converting “areas that are traditionally humid, such as valleys and tropical forests, into environments where small fires can quickly escalate to large-scale megafires before intervention can be done.” This is a direct effect of climate change by multiplying weather conditions conducive to fires, such as high temperatures, low relative humidity and extensive droughts. “These conditions, in turn, increase the dryness of the plant material, thus increasing the number of days in which the vegetation is available to burn throughout the year,” completes the scientist.
The fire season has not stopped lengthening since the beginning of the century. Globally, it has increased by up to a third. In some regions it has grown by around 50%, such as in the Mediterranean region, California or southeastern Australia, areas that have traditionally belonged to the kingdom of fire. But in other less accustomed areas, such as Canada, the risk period has grown by up to 70% and in the Amazon rainforest, it has directly doubled. In the latter, a clamp on the forests is taking place. On the one hand, there is the traditional deforestation (both legal and illegal) of large areas to convert them into grazing areas for livestock or agricultural areas for the cultivation of products for export. On the other hand, climate change is, as has been seen, increasing flammability. “Under normal conditions, tropical forests like the Amazon are very humid, have a short dry season and are very resistant to fire,” he told this newspaper. However, the combination of climate and deforestation is being lethal. The jungle, increasingly thinned out, increasingly fragmented, is losing moisture until it is exposed to fire.
The process is somewhat different in boreal forests. Here the fires were part of the landscape. Almost always caused by a lightning strike, it was the ecosystem itself, rich in humidity, that regulated it. But the starting conditions have changed. Alaska, Canada, the northern Nordic countries and the forested part of Siberia have been experiencing drought for years against a global backdrop of rising temperatures. The dryness and the enormous availability of fuel heralded disaster. Since the beginning of this decade, more than 10 million hectares of Siberian taiga have burned. Much more than that figure burned in the summer of 2023 on Canadian lands, with almost 20 million hectares. The summer of 2018, with temperatures up to 10 degrees above average, was the worst in number of fires and hectares burned in Sweden since they have records.
Boreal forests are fertile ground for megafires. With enormous areas of trees, far from population centers and, therefore, from fire-fighting infrastructure, dryness and the increase in dry storms, that is, lightning, which is promoting climate change completes the framework. All you need is a match, in the shape of a lightning bolt, for disaster. And once they start, there is nothing and no one that can stop them, only nature itself in the form of rain. “The fires in Canada or Australia are associated with unprecedented levels of atmospheric drought,” says professor at the University of Lleida, Victor Resco. This drought is superimposed on the meteorological drought (lack of rain) and that of the trees themselves (which lose water through evapotranspiration). Research published at the end of 2023 showed that Europe’s air is the driest in the last 400 years.
Resco highlights another element that has changed, the intensity of these gigantic fires. And he uses a comparison to find out what it is: “A bathroom heater, the kind that turns red, releases 2 kilowatts (kW) of energy in the form of heat. Well, imagine 5,000 of these heaters placed in one linear meter. That’s 10,000 kW. The EMU or NATO can come, they will not turn it off.” And he adds, “well, sixth generation fires can release 100,000 and up to 150,000 kW.” The one that devastated the Pedrógão Grande area, in Portugal, in 2017 and killed 66 people “was in that range, releasing energy equivalent to 27 atomic bombs.”
The challenge is such that an almost teleological discussion has broken out between fire ecologists and fire prevention system managers. Until now there were two strategies. One, that of Europeans and Americans, whose objective is to accumulate all possible infantry and technology to quell each attempt that breaks out. The other, which is based on traditional knowledge and has been applied in Australia, is more committed to controlled burning. “Traditional fire management practices, such as those carried out by indigenous communities, usually involve low-intensity controlled burning in specific areas, that is, in a patchy manner, creating a mosaic of burned and unburned areas,” explains Yebra, from the Australian National University. This helps reduce the buildup of flammable organic matter. “In contrast, modern fire management has tended to suppress these controlled fires in favor of more intensive methods of suppression and prevention.”
The problem with the Western approach is that continued fire suppression has led to significant fuel accumulation on many landscapes. In fact, there are experts who blame the success of this approach in the past on the fires of the present. “It is the paradox of extinction, as you put out fires, the risk of a megafire occurring increases,” recalls Resco, from the University of Lleida. There are many experts who point to this as a dance partner for climate change to explain the fires that California suffers every year.
Environmentalologist Emilio Chuvieco is not convinced by the idea of the pyrocene. “It happens as with the idea of the Anthropocene of geologists. Whether a distinctive mark of human activity across the planet is found in the stratum is debatable,” he says. In fact, the official entry into the supposed new era has been put on hold. “It is true that there are large fires, but there is no data to affirm that the relationship between man and fire has changed,” he adds. “There is no increase in fires on a global scale,” he recalls. In fact, the total burned area has decreased, especially because fires in the African and American savannahs, previously very common, have been reduced by the conversion of millions of hectares into crop areas. “What is not known is whether there is an increase in extreme events,” he adds. Chuvieco, director of the chair of environmental ethics at the University of Alcalá de Henares, is the scientific leader of FirEUrisk, a project promoted by the European Commission 2022 to determine and minimize the risk of extreme fires in Europe. Regarding the discussion between extinction or fighting fire with fire, he considers that, at least in Europe, with the demographic density and infrastructure, extinction programs are mandatory.
You can follow SUBJECT in Facebook, x and instagramor sign up here to receive our weekly newsletter.
#Pyrocene #era #inextinguishable #fires