The increasing effects of climate change is creating greater atmospheric demand for water, which in turn is leading to a heightened risk of major wildfires sparking in forests around the world, according to a recent study from scientists at the University of Melbourne.

The study, Forest fire threatens global carbon sinks and population centres under rising atmospheric water demand, found that in all types of forests, there is a strong link between fire activity and vapor pressure deficit (VPD), which is a measure of the atmosphere’s thirst. VPD describes the difference between how much moisture is in the air, and how much moisture the air can hold when it’s saturated. Notably, warmer air can hold more water, which means that VPD increases with rising temperatures due to climate change. Ultimately, the researchers found that in different kinds of forests across the world there is a strong link between fire activity and how thirsty the air is at a daily timescale. In other words, wildfires are more likely above a certain threshold in VPD.

The study’s leader author, Dr. Hamish Clarke from the University of Melbourne FLARE Wildlife Research group, said that all around the world we’re likely to see more of the conditions under which forests dry out and become flammable. The results of this research are supported by past studies that WaterISAC have reported on, such as a UN report that found climate change could increase the risk of wildfires by 30 percent by 2050. Another study observed the length of the traditional fire season is increasing in conjunction with climate change. “Without strong climate action, there will be many more days each year – at least 30 – when Earth’s forests cross over into this critical flammability zone,” said Dr. Clarke. “This means we’re likely to see more major fires, with all the risks that come with them.” Access the original study here or read a related article at the University of Melbourne.