Study Says Rising Temperatures Boost Fire-Prone Days
A new study reveals that the number of days characterized by hot, dry, and windy conditions—conditions that are perfect for igniting extreme wildfires—has nearly tripled worldwide over the past 45 years, with an even more pronounced increase observed in the Americas. Researchers calculated that more than half of that increase is attributed to human-caused climate change. As the world continues to warm, an increasing number of regions around the globe are at risk of experiencing simultaneous wildfires due to the phenomenon of synchronous fire weather, characterized by multiple locations having the ideal conditions for combustion. According to the authors of a study published in Wednesday’s Science Advances, countries may lack sufficient resources to extinguish all the fires emerging, and assistance from neighboring nations may be unlikely as they contend with their own crises.
According to the study, from 1979 and for the subsequent 15 years, the world experienced an average of 22 synchronous fire weather days annually, with flames remaining confined to extensive global regions. In 2023 and 2024, it was up to more than 60 days a year. “These sorts of changes that we have seen increase the likelihood in a lot of areas that there will be fires that are going to be very challenging to suppress,” said John Abatzoglou. The researchers focused not on actual fires, but rather on the prevailing weather conditions: warm temperatures, strong winds, and dry air and ground. “It increases the likelihood of widespread fire outbreaks, but the weather is one dimension,” said Cong Yin Merced. Oxygen, fuel like trees and brush, and ignition sources such as lightning, arson, or human accidents are the other significant components that contribute to fires.
This study holds significance as extreme fire weather is the main, though not the sole, contributor to the rising fire impacts worldwide, stated fire scientist Mike Flannigan of Thompson Rivers University in Canada, who was not involved in the research. “And it’s also important because regions that used to have fire seasons at different times and could share resources are now overlapping,” he said. Abatzoglou stated: “And that’s where things begin to break.” Yin stated that over 60 per cent of the worldwide rise in synchronous fire weather days can be linked to climate change resulting from the combustion of coal, oil, and natural gas. He and his colleagues are aware of this due to their use of computer simulations, which allowed them to compare the events of the last 45 years to a hypothetical scenario devoid of the heightened greenhouse gases resulting from fossil fuel combustion.
Between 1979 and 1988, the continental United States experienced an average of 7.7 synchronous fire weather days annually. However, in the past decade, that average increased to 38 days per year, as stated by Yin. However, that pales in comparison to the southern half of South America. The region recorded an average of 5.5 synchronous fire weather days annually from 1979 to 1988; in contrast, the last decade has seen this figure increase to 70.6 days per year, with a notable 118 days occurring in 2023. Among the 14 global regions, only Southeast Asia experienced a decline in synchronous fire weather, likely due to increasing humidity in the area, Yin stated.
