Asteroid Impacts Could Have Triggered Earth's "Snowball" Periods, Study Suggests

Throughout Earth's history, it has experienced multiple "Snowball" periods where the entire planet was covered in ice for extended periods. The origins of these frigid epochs have long been a subject of debate among scientists. However, a recent study suggests that massive asteroids striking Earth could have played a role in triggering these icy conditions.

The research, published in the journal Science Advances, was conducted by a team of experts from Yale University, the University of Chicago, and the University of Vienna. Previous theories pointed to a decrease in greenhouse gases as the culprit for the onset of ice ages. Still, researchers were eager to explore alternative possibilities.

Lead author Minmin Fu, a Richard Foster Flint Postdoctoral Fellow at Yale's Department of Earth and Planetary Sciences, explained, "We decided to explore an alternative possibility. What if an extraterrestrial impact caused this climate change transition very abruptly?" Using a climate model, the scientists simulated the aftermath of asteroid impacts during four different periods in Earth's history: the Preindustrial era, the Last Glacial Maximum, the Cretaceous period, and the Neoproterozoic era. Their findings revealed that while asteroid impacts were not likely to trigger a snowball period during warmer periods like the Cretaceous and Preindustrial era, they could have done so during the colder Last Glacial Maximum and Neoproterozoic periods.

Co-author Alexey Fedorov, a professor of ocean and atmospheric sciences at Yale, expressed surprise at the results, stating, "What surprised me most in our results is that, given sufficiently cold initial climate conditions, a 'Snowball' state after an asteroid impact can develop over the global ocean in a matter of just one decade." This study sheds new light on the potential role of asteroid impacts in Earth's climatic history and opens up avenues for further research in understanding the factors that contribute to the planet's icy past.