Scientists are worried that wildfires might burn out of control in Siberia while the Russian military units that normally keep them in check are dispatched to Ukraine.

“Because the largest fires often need military aircraft to spot and verify the satellite or community reports, [and to] support and fight in Siberia, it is questionable that this capacity will even be available during the summer if the war continues,” Jessica McCarty, a climate researcher at the Miami University of Ohio, told Axios in an email.

“So, either there will be more fires… or these aircraft and personnel will be taken away from the western front and brought to Siberia.”

Russian wildfires are a major source of carbon dioxide emissions and can hasten sea ice melt by spewing soot into the Arctic. The fires are in some cases ongoing and can smoulder in peat-rich soil throughout the winter to re-emerge as “zombie fires” in the spring. These effects form a feedback loop where the accelerating influence of climate change makes the region more prone to fires, reports Axios.

“With drying, fires are burning into northern peat deposits and releasing old carbon, further amplifying atmospheric carbon dioxide levels,” said Mike Waddington, a climate researcher at McMaster University. “It’s a climate change double whammy.”

Firefighting crews and equipment in Siberia are typically assembled with military aircraft and personnel, which are stretched thin in the region even during peacetime. But while the blazes are growing more severe, firefighting forces are lacking as Russian soldiers are siphoned to the front lines in Ukraine.

U.S. and European sanctions are also acting as a damper on international collaboration between Western and Russian scientists to monitor and study the fires, so Western information now has to rely on satellite monitoring, Axios says.