Scientists discover the global paradox of forest fires

Over the past two decades, the total burned area has decreased, even if human impacts have worsened.

Scientists from the University of California in Irvine, as well as international collaborators, have identified a striking paradox in the world models of forest fires. Between 2002 and 2021, the overall area of ​​burnt land in the world fell by 26%. However, during this same period, the number of people in direct contact with forest fires increased by almost 40%.

The results, published in ScienceUnderline a statistic that may surprise those who mainly follow Western media. While catastrophic forest fires in the United States, Canada and Australia frequently make international titles, the study shows that 85% of all exposure to human forest during these years has taken place in Africa.

In Africa, only five countries – Congo, South -Soudan, Mozambique, Zambia and Angola – were responsible for half of the total exhibition in the world of forest fires. In comparison, the combined share for the United States, Europe and Australia was less than 2.5%.

“Nevertheless, the Western United States and in particular California are intense firestones on a global scale,” said the main author Mojtaba Sadegh, associate professor of civil engineering at Idaho Wood state university who obtained a doctorate. In civil and environmental engineering at UC Irvine in 2015. “Our study published previously shows that California knows a disproportionate part of the impacts of American fire, representing 72% of human exhibitions despite 15% of the country’s burnt area.”

Growing human exhibition

The researchers analyzed the population data and more than 18.6 million fire registers from 2002 to 2021 to note that around 440 million people worldwide were exposed to a forest fire encroaching on their house during this period – a number roughly equivalent to the entire population of the European Union. They discovered that human exposure to forest fires increased by 7.7 million people, an average of 382,700 people per year during the study period. This increase in human exposure was not caused by a world leap in fire activity, but mainly by population growth and migration in the landscapes subject to fires.

Another factor illuminated by research is a significant increase in the intensity of forest fires in North and South America. This is linked to the amplification led by climate change of “fire time”, which includes conditions such as increased heat, drop in humidity and strong winds.

Extreme fire time has increased by more than 50% in the past four decades worldwide.

When combined with human activities such as land development and historical fire suppression practices, this trend has led to an increase in destructive fire risk in regions like California. The frequency of conditions conducive to forest fire fires (such as fires from Los Angeles 2025) quadrupled from 1990 to 2022 through the State.

Regional exposure differences

In Europe and Oceania, the study noted a decrease in exhibitions to the forest, mainly due to changes in the population of rural areas to urban areas. This highlights the way in which social and environmental factors play a critical role in the training of forest risks.

“The global paradox of the decrease in the burning zone and the increased human impacts that we have revealed … is largely due to an increasing overlap between human establishments and the landscapes subject to fires,” said co-author Amir Aghakouchak, professor of civil and environmental genius of the IRVINE.

Highlighting a growing human vulnerability to forest fires – in particular in regions that receive little international attention – research emphasizes the urgent need for proactive mitigation strategies to protect communities against the emerging threat of forest fires. These include vegetation management techniques such as prescribed fires, public education and engineering solutions to reduce the allations caused by humans.

“While climate change intensifies fires and the world populations continue to develop in zones subject to fires, proactive attenuation will be more and more critical to reduce the risk of future forest disasters,” said Aghakouchak.

Reference: “The increase in the world’s human exposure to forest fires despite the drop in the burnt zone” by Seyd Teymoor Seydi, John T. Abatzoglou, Matthew W. Jones, Crystal A. Kolden, Gabriel Filiptelli, Matthew D. Hurteau, Amir Aghakouchak, Charles H. Luce, Chiyuan Miao and Mojtaba Sadegh, 21 Science.
DOI: 10.1126 / Science.adu6408

The funding was provided by the US National Science Foundation.

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