Excerpt: Burning fossil fuels may have stopped the Earth from entering another ice age, a new study suggests. The research, published Thursday in the journal Science, uses samples of ancient vegetation and rock records to analyze the growth—and sudden retreat—of an ice cap that is the last vestige of an ice sheet that once covered much of North America.
“A question that’s in the popular consciousness is, have we caused enough global warming to stop the next ice age from happening?” says Andrew Wickert, an associate professor of environmental science at the University of Minnesota Twin Cities, who was not involved in the research. The new research shows that “even as we were just starting to ramp up emissions, we’ve already done enough damage to cause the major North American ice sheet to already start retreating. That’s significant.”
