Triassic climate shift sparked thousand-year megafires across Europe

Prolonged droughts during the early Triassic led to the loss of conifer forests, which were replaced by fire‑prone ferns. Once dried, these ferns acted as fuel for massive, persistent wildfires that burned for more than a thousand years, representing one of the greatest fire hazards in Earth's history.

Researchers from the University of Utrecht examined drill‑core samples from Germany, Luxembourg, Denmark and the United Kingdom. Pollen and plant‑remnant analysis confirmed repeated spikes in fire activity that coincided with the expansion of fern savannas. The study links these megafires to a combination of severe aridity, rising temperatures and the emergence of easily ignitable vegetation during the first 50 million years of the Mesozoic era, roughly 251–201 million years ago.