A team of researchers has taken a stance in the ongoing “Snowball Earth” debate regarding the potential cause of planet-wide ice ages that occurred in the ancient past. Their latest study suggests that these extended periods of global glaciation may have been abruptly triggered by massive asteroid impacts on Earth’s surface.
Climate experts have long understood that if the Earth were to become cold enough, the high reflectivity of snow and ice could set off a self-perpetuating cycle, leading to more ice and even lower temperatures until the entire planet was encased in ice. This phenomenon occurred at least twice during the Neoproterozoic era, between 720 and 635 million years ago.
However, attempts to explain the cause of these “Snowball Earth” events have been inconclusive. Most theories have focused on the idea that a decline in greenhouse gases in the atmosphere triggered the onset of global glaciation.
“We wanted to consider an alternative explanation,” explained Minmin Fu, the lead author of the study and the Richard Foster Flint Postdoctoral Fellow in the Department of Earth and Planetary Sciences at Yale’s Faculty of Arts and Sciences. “What if an extraterrestrial impact caused this abrupt climate shift?”
Using an advanced climate model that simulates atmospheric and ocean circulation, as well as the formation of sea ice, the researchers explored various scenarios. This model is the same type used to forecast future climate patterns.
2024-02-10 02:00:05
Link from phys.org