A new study published in Nature Ecology & Evolution shows that the number and intensity of the most extreme wildfires on Earth have doubled over the past two decades.

The authors of the new study, researchers at the University of Tasmania, first calculated the energy released by different fires over 21 years from 2003 to 2023. They did this by using a satellite-based sensor that can identify heat from fires, measuring the energy released as “fire radiative power.”

The researchers identified a total of 30 million fires (technically 30 million “fire events,” which can include some clusters of fires grouped together). They then selected the top 2,913 with the most energy released, that is, the 0.01 percent “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, the Earth has experienced the six years with the highest number of extreme wildfires (all years except 2022).