Decoding Dinosaur Extinction: Meteorite Impact or Volcanic Eruption

For decades, scientists have debated whether the mass extinction of dinosaurs was caused solely by the Chicxulub meteorite impact or if massive volcanic eruptions also played a significant role.

Approximately 66 million years ago, a meteorite struck the Gulf of Mexico, an event widely recognized as the end of the dinosaur era. However, some researchers have long questioned whether colossal volcanic eruptions on the Indian subcontinent might have accelerated their demise. These eruptions released vast amounts of carbon dioxide, sulfur, and ash, dramatically altering Earth's climate in ways distinct from the meteorite impact.

A recent study published in Science Advances by climate scientists from Utrecht University in the Netherlands and the University of Manchester in the UK provides compelling evidence that, despite their significant impact on global climate, volcanic eruptions had minimal influence on the mass extinction of dinosaurs.

The research team reconstructed temperature fluctuations during the periods of volcanic activity and the meteorite impact by analyzing fossil molecules preserved in ancient peat from the United States. Their findings reveal that volcanic eruptions caused a temperature drop of at least 5°C around 30,000 years before the meteorite impact, likely due to sulfur emissions blocking sunlight. However, temperatures rebounded to pre-eruption levels approximately 20,000 years before the meteorite struck, suggesting the climatic effects of the eruptions had largely dissipated.

The researchers concluded that while volcanic emissions of carbon dioxide and sulfur had profound ecological consequences, these events occurred well before the meteorite impact and likely played only a minor role in the dinosaurs' extinction.