Stanford University Report: Current Warming Faster Than Any Change Post-KT Extinction
EDIT
If the Earth stays on its current course without reversing greenhouse gas emissions, and global temperatures rise 5 degrees Celsius, as scientists say is possible, the pace of change will be at least 50 times and possibly 100 times swifter than what's occurred in the past, Field said. The numbers are imprecise because the comparison is to an era 55 million years ago, he said.
"The planet has not experienced changes this rapid in 65 million years," Field said. "Humans have never seen anything like this." Field, in the school's Department of Global Ecology with the Carnegie Institution for Science, and Noah Diffenbaugh, an associate professor of environmental Earth system science, reviewed and synthesized existing research on climate change for a special issue of Science: "Natural Systems in Changing Climates."
They looked at climate events or major transitions that have happened on Earth since the extinction of the dinosaurs. Those include the period when the Earth emerged from an ice age. Temperatures then increased between 3 and 5 degrees Celsius, similar to the amount scientists say is possible with ongoing climate change. But that change happened over about 20,000 years, the scientists said, and not decades as is happening now.
They also looked at a period when global temperatures dropped 11 to 12 degrees over a period 52 million to 34 million years ago. "That's a larger change in global temperature than what's likely to occur over the next century, but it happened over 18 million years," Diffenbaugh said. "So it was a high-magnitude but relatively low-rate event.
EDIT
http://www.scientificamerican.com/article.cfm?id=todays-climate-change-proves-much-faster-than-changes-in-past-65-million-years
= new reply since forum marked as read
