More than 320 million trees are taken out by lightning strikes every year, a figure that is exponentially higher once accounting for trees engulfed by lightning-related firestorms. That is according to a new study, published in Global Change Biology, which for the first time has developed a global model for calculating lightning-caused tree deaths.
Led by Andreas Krause from the Technical University of Munich, researchers claim that policymakers have underestimated the impact of lightning strikes for decades. And if lightning strikes become more frequent as the climate warms -as many projections suggest – this overlooked threat could grow even bigger.
Dubbed “the silent killer in the woods,” researchers said that when a tree gets hit, the damage can be internal – its tissue fried from the inside out. And whilst the tree might stay standing for a while, it is slowly dying without any outward sign of what happened. In dense forests, those deaths are lost in the canopy and blend into the background. Scientists had long known that lightning was killing trees, but they didn’t know how many. Field observations in individual forests offered glimpses, but there was no way to connect the dots globally.
However, Krause’s team took a different approach. Instead of relying on fieldwork, they developed a global vegetation model and combined it with data on the global distribution of lightning. Next, they examined how trees respond to being struck, including the number of survivors, the number of fatalities, and the duration of the recovery process, assessing when lightning does its most damage and how it affects forest health on a scale of goals: “We’re now able not only to estimate how many trees die from lightning strikes annually, but also to identify the regions most affected and assess the implications for global carbon storage and forest structure,” Krause said.
Beyond killing trees, lightning strikes also shake up the carbon balance.
According to the study, lightning-related tree deaths emit somewhere between 0.77 and 1.09 billion tons of CO₂ per year…nearly as much as the 1.26 billion tons released by the burning of living plants in wildfires. To put that in perspective, the total carbon emissions from wildfires each year – including deadwood and soil material – amount to approximately 5.85 billion tons. Currently, most tree loss is occurring in tropical forests. These areas experience high lightning activity year-round, particularly in regions such as the Congo Basin and the Amazon. Tropical trees also tend to be taller and more likely to get struck, but the pattern could shift.
“Most climate models project an increase in lightning frequency in the coming decades, so it’s worth paying closer attention to this largely overlooked disturbance,” Krause said, adding that the increase won’t be spread evenly. Models predict that lightning will become more frequent in temperate and boreal regions too – places like Canada, Russia, and parts of the U.S., where trees haven’t historically had to deal with much lightning. Forests already stressed by drought, heat, and pests may soon face another challenge. And since trees in colder regions tend to grow more slowly, their recovery from lightning-related losses could take decades.
And unlike wildfires, which are often visible from satellites and leave behind large scars, lightning deaths can be subtle. They happen one by one, scattered across the forest floor. In effect, this makes them much harder to monitor—and easier to ignore. Wood Central understands that the study marks the first attempt to measure the damage, suggesting a rethink of how forests are modelled. “Lightning might not be as showy as a wildfire, but its quiet impact could have lasting effects on the world’s forests – and the carbon cycle they support,” the researchers said.
For more information: Simulating Lightning-Induced Tree Mortality in the Dynamic Global Vegetation Model, Global Change Biology, Andreas Krause, Konstantin Gregor, Benjamin F. Meyer, Anja Rammig. First published: 24 June 2025 https://doi.org/10.1111/gcb.70312
