A groundbreaking study estimates that lightning strikes cause the death of up to 320 million trees every year. The researchers, from the Technical University of Munich (TUM), used novel mathematical models to calculate this figure. Their analysis includes only tree deaths directly caused by lightning and excludes those killed indirectly due to wildfires.
The study combines data from camera observations, drone surveys, and ground investigations in tropical forests to estimate tree mortality rates. In a temperate forest in Panama’s Barro Colorado Island (BCI), the researchers found that lightning strikes can cause a “flashover” effect, killing up to 3.5 trees on average per strike.
The team applied their validated model to other global forests and incorporated datasets on lightning frequency and density. The results suggest that 286-328 million lightning strikes occur each year, resulting in the death of 301-340 million trees over a 20-year period. While natural causes kill around 50 billion trees annually, lightning-induced tree deaths account for only 0.69% overall.
However, these numbers may be increasing due to rising lightning frequency. In tropical regions, lightning-induced tree mortality is currently high, but models predict that this could become more relevant in temperate and boreal forests as lightning frequency increases by 25-50%. The study’s lead author notes that tree mortality, including lightning-induced deaths, is often underestimated and should be included in future carbon calculations.
This research has significant implications for understanding forest structure and carbon storage on a global scale. By accurately quantifying the impact of lightning strikes, scientists can improve their models and better predict the effects of environmental changes on forests.
Source: https://www.sciencealert.com/lightning-kills-way-more-trees-than-you-would-ever-believe