Lightning Lightning over the Ionian Sea, in Greece. © Stathis Koutsiaftis

A new study estimates that lightning kills about 320 million trees around the world every year.

Researchers from the Technical University of Munich (TUM) discovered that lightning has a much bigger effect on forests than previously known. Using a new model, they estimated—for the first time—how many trees die directly from lightning strikes. This number does not include trees lost to wildfires started by lightning.

Image captured by Stathis Koutsiaftis, on the night of August 7, 2016. This view was taken from a beach overlooking the Ionian Sea, in Greece. 

Until now, it has been difficult to measure the number of trees that lightning kills globally. Most studies only looked at small areas. But the TUM team created a method to estimate worldwide lightning-related tree deaths by combining satellite lightning data and a global forest model.

Their results show that lightning is a much more serious threat to trees than once thought, and with lightning expected to increase due to climate change, the problem could get worse.

Andreas Krause, lead author of the study and researcher at the Chair of Land Surface–Atmosphere Interactions, explains:

“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.”