Title: Ice Age, Not Fire: Study”>Global Wildfires Likely Played Key Role in Abrupt Climate Changes in the Last Ice Age
A recent study published in the journal Nature has shed new light on the role of wildfires in past abrupt climate changes during the last ice age. The study, led by Ben Riddell-Young, a PhD student at Oregon State University (OSU), suggests that there were brief and intense periods of global wildfire activity that occurred simultaneously with other significant climate shifts.
The study analyzed ancient methane trapped in ice cores from Antarctica, which can provide insights into global climate conditions during the last ice age, which ended around 11,000 years ago. Previous research has shown that atmospheric methane levels rose dramatically during brief warming events known as Dansgaard-Oeschger and Heinrich events. These events were marked by rapid regional temperature changes, shifts in tropical rainfall patterns, and methane spikes.
“This study shows that there were brief, intense periods of burning happening at the same time as these other big climate shifts,” said Edward Brook, a paleoclimatologist at OSU and a co-author of the study. “It’s something we haven’t seen before in the climate data.”
The study found that these wildfire events likely played a significant role in driving the abrupt climate changes of the last ice age. Riddell-Young used a technique he developed to extract air from ancient ice samples and analyze the isotopic composition of methane using a mass spectrometer. The isotopic signatures indicated that the methane spikes were caused by increased wildfires.
“This study shows that we might not be fully considering how wildfire activity could change as the climate warms and rainfall patterns shift,” said Riddell-Young, who is now a postdoctoral researcher at the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder.
The findings have important implications for understanding modern abrupt climate changes, as the Earth’s climate continues to warm at an unprecedented rate. Further research is needed to better understand the role of wildfires in climate patterns, including their impact on carbon dioxide and other greenhouse gas levels in the atmosphere.
“Understanding the significance of these burn events to the carbon cycle is one of the next steps in this research,” added Brook.
Source:
Ben Riddell-Young, et al. Abrupt shifts in biomass burning during the last glacial period, Nature(2025). DOI: 10.1038/s41586-024-08363-3
