LSU part of study of icy Earth
Print
Email
Save
Share
Del.icio.us
Digg
Facebook
Reddit
Earth may have been completely covered in ice many millions of years ago, according to LSU-supported research.
The study offered evidence of the so-called “Snowball Earth” hypothesis that ice blanketed the planet during the Cryogenian period more than 630 million years ago.
The findings of LSU scientist Huiming Bao with colleagues from the University of California at Los Angeles and from China were recently reported in the scientific journal Nature.
In light of the increasing environmental stresses humans have placed on Earth, Bao said there is a critical need to understand how a complex system like Earth’s can be expected to react.
“There is an old saying that the best way to know a person’s character is to put him or her under pressure and see how he reacts,” Bao said in a prepared statement. “This is the same situation. The best way to learn more about our Earth system is to see how it responded to extreme conditions in the past.”
Bao and his group used a new parameter called “sulfate oxygen-17 anomaly” to measure atmospheric re-cords. Oxygen-17 is usually not measured by scientists who study Earth rocks because they were originally believed to be exclusively extraterrestrial in nature, coming only from specific types of asteroids, Bao said.
What is striking is the timing of the negative anomalies, Bao said. There is a spike in the depletion right when global glaciation came to an abrupt end approximately 635 million years ago.
Bao and his colleagues proposed that the spike was caused by an extremely high atmospheric carbon dioxide concentration, at least 40 times the modern level. That is what the “Snowball Earth” hypothesis predicted when the oceans were frozen over for millions of years.
The study offered evidence of the so-called “Snowball Earth” hypothesis that ice blanketed the planet during the Cryogenian period more than 630 million years ago.
The findings of LSU scientist Huiming Bao with colleagues from the University of California at Los Angeles and from China were recently reported in the scientific journal Nature.
In light of the increasing environmental stresses humans have placed on Earth, Bao said there is a critical need to understand how a complex system like Earth’s can be expected to react.
“There is an old saying that the best way to know a person’s character is to put him or her under pressure and see how he reacts,” Bao said in a prepared statement. “This is the same situation. The best way to learn more about our Earth system is to see how it responded to extreme conditions in the past.”
Bao and his group used a new parameter called “sulfate oxygen-17 anomaly” to measure atmospheric re-cords. Oxygen-17 is usually not measured by scientists who study Earth rocks because they were originally believed to be exclusively extraterrestrial in nature, coming only from specific types of asteroids, Bao said.
What is striking is the timing of the negative anomalies, Bao said. There is a spike in the depletion right when global glaciation came to an abrupt end approximately 635 million years ago.
Bao and his colleagues proposed that the spike was caused by an extremely high atmospheric carbon dioxide concentration, at least 40 times the modern level. That is what the “Snowball Earth” hypothesis predicted when the oceans were frozen over for millions of years.
 | ||||
| Most Popular | Most Emailed | Hot Topics | ||
