A federal advisory committee appointed by the Obama administration to produce a report on climate change says that if Earth’s climate were still “primarily controlled by natural factors”—rather than by man-made global warming—then the next ice age would occur within the next 1,500 years.
But now, because of humans, the committee says, the next ice age has been “delayed indefinitely.”
“Confirmation of what are called Milankovich cycles (cyclical changes in the Earth’s orbit that explain the onset and ending of ice ages) led a few scientists in the 1970s to suggest that the current warm interglacial period might be ending soon, plunging the Earth into a new ice age over the next few centuries,” the advisory committee said in a draft report released last month.
“Scientists continue to study this issue today; the latest information suggests that, if the Earth’s climate were being controlled primarily by natural factors, the next glaciation would begin sometime in the next 1,500 years,” says the report. “However, humans have so altered the composition of the atmosphere that the next glaciation has now been delayed indefinitely.”