THIS ARTICLE IS republished from The conversation under Creative Commons License.
It seems we are getting used to the Earth being on fire. Recently, More than 70 forest fires burned simultaneously in Greece. In early 2024, Chile suffered its worst wildfire season in history, with More than 130 people diedLast year, record-breaking wildfires in Canada raged between March and November, and in August, flames devastated the island of Maui in Hawaii. The list goes on.
Watching the news, it certainly seems like extreme and catastrophic wildfires are occurring more frequently, and sadly, this feeling has now been confirmed as correct. New study A study published in Nature Ecology & Evolution shows that the number and intensity of the most extreme wildfires on Earth have doubled in the past two decades.
The authors of the new study, researchers from the University of Tasmania, first calculated the energy released by different fires over 21 years, from 2003 to 2023. They did this using a satellite based sensor which can identify the heat of fires, measuring the energy released as “radiative power of the fire”.
The researchers identified a total of 30 million fires (technically, 30 million “fire events,” which can include some clustered groups of fires). They then selected the 2,913 largest wildfires with the highest energy release—or 0.01 percent of the “most extreme” wildfires. Their work shows that these extreme wildfires are becoming more frequent, with their number doubling over the past two decades. Since 2017, Earth has experienced the six years with the highest number of extreme wildfires (every year except 2022).
Importantly, these extreme wildfires are also becoming even more intense. Those classified as extreme in recent years released twice as much energy as those classified as extreme at the beginning of the period studied.
These findings are consistent with other recent evidence that wildfires are getting worse. For example, the area of forest burned each year is increasing slightly, leading to a Increase in forest carbon emissions. (The total area of land burned each year is actually decreasingdue to a decrease in fires in grasslands and croplands, but these fires are of lower intensity and emit less carbon than forest fires).
Severity of the burn—an indicator of how severely a fire damages an ecosystem—is also worsening in many regions, and the percentage of burned land affected by high-severity fires is also increasing globally.