An imaginary representation of what the Earth looked like when it was a snowball Earth. It looks like a ‘white Earth’ rather than a blue Earth. Provided by Wikimedia.
A research model has been presented that suggests that if an asteroid collision occurred at a time when the Earth’s temperature dropped significantly, it could have triggered a ‘snowball Earth’. Snowball Earth refers to the point in time when it is colder than the Ice Age and the entire Earth looks like a snowball.
Earth is known to have experienced several ice ages. It is presumed that there was a time when the entire Earth, including the equatorial region, was completely covered in ice, which is called ‘Snowball Earth’. It is estimated that the snowball Earth, which froze all the way to the equator, was formed between 720 million and 635 million years ago. It is unclear how this period was formed.
A joint research team from Yale University, the University of Chicago, and Vienna University of Austria published research results in the international academic journal ‘Science Advances’ on the 10th, suggesting that the Snowball Earth may be related to an ice age and an asteroid impact. Through simulation work, the research team confirmed that a snowball Earth could be formed if an asteroid impacts when the Earth’s climate reaches a very low state, such as during the Ice Age.
The Chicxulub crater, which occurred 66 million years ago when an asteroid hit Mexico’s Yucatan Peninsula, is associated with the Earth’s extreme cooling and the mass extinction event at the end of the Cretaceous period. However, at the time, no evidence was found that an asteroid impact created the snowball Earth.
The research team used ‘CESM’, a global climate simulation, to predict at what point the snowball Earth would be born. Assuming that four climates occurred, we recreated a situation where an asteroid collision occurred, like the Chicxulub incident. The four climates were set as pre-industrial ‘before 1850’, the last maximum ice age ‘about 20,000 years ago’, the Cretaceous period, and the Neoproterozoic climate.
As a result of modeling the changes in solar radiation that occur when an asteroid impact occurs in each climate, it was found that a snowball Earth could be triggered during the Last Ice Age and the Neoproterozoic Era. It was found that a snowball Earth could not have occurred during the pre-industrial and Cretaceous periods, which had relatively mild climates. The explanation is that the Chicxulub crater occurred during the Cretaceous period, so the snowball Earth would not have occurred.
The research team interpreted, “For the Earth to reach an extreme cooling period like Snowball Earth, the Earth’s temperature must be fundamentally low.” Given that today’s Earth is getting hotter due to global warming, it can be evaluated as a time when the possibility of reaching a snowball Earth is slim.
