Ancient ‘Snowball Earth’ thawed out in a flash
https://www.sciencemag.org/news/2019/04/ancient-snowball-earth-thawed-out-flash
Source: By Lucas Joel, Science Magazine.
Excerpt: More than half a billion years ago, our planet was a giant snowball hurtling through space. Glaciers blanketed the globe all the way to the equator in one of the mysterious “Snowball Earth” events geologists think occurred at least twice in Earth’s ancient past. Now, scientists have found that the final snowball episode likely ended in a flash about 635 million years ago—a geologically fast event that may have implications for today’s human-driven global warming. The ice, which built up over several thousand years, “melted in no more than 1 million years,” says Shuhai Xiao, a paleobiologist at Virginia Polytechnic Institute and State University in Blacksburg who was part of the team that made the discovery. That’s the blink of an eye in our planet’s 4.56-billion-year history, suggesting the globe reached a sudden tipping point, Xiao says. Although the team doesn’t know for certain what caused it, carbon dioxide emitted by ancient volcanoes may have triggered a greenhouse event, causing the ice sheets to thaw rapidly....
Source: By Lucas Joel, Science Magazine.
Excerpt: More than half a billion years ago, our planet was a giant snowball hurtling through space. Glaciers blanketed the globe all the way to the equator in one of the mysterious “Snowball Earth” events geologists think occurred at least twice in Earth’s ancient past. Now, scientists have found that the final snowball episode likely ended in a flash about 635 million years ago—a geologically fast event that may have implications for today’s human-driven global warming. The ice, which built up over several thousand years, “melted in no more than 1 million years,” says Shuhai Xiao, a paleobiologist at Virginia Polytechnic Institute and State University in Blacksburg who was part of the team that made the discovery. That’s the blink of an eye in our planet’s 4.56-billion-year history, suggesting the globe reached a sudden tipping point, Xiao says. Although the team doesn’t know for certain what caused it, carbon dioxide emitted by ancient volcanoes may have triggered a greenhouse event, causing the ice sheets to thaw rapidly....