Last time carbon dioxide levels were this high: 15 million years ago

You must go back 15 million years to find carbon dioxide levels as high as they are today, Earth scientists report. “The last time carbon dioxide levels were apparently as high as they are today and sustained at those levels, global temperatures were five to 10 degrees Fahrenheit higher than they are today,” said Aradhna Tripati, UCLA assistant professor of Earth and Space Sciences and lead author. “The last time carbon dioxide levels were apparently as high as they are today — and were sustained at those levels — global temperatures were 5 to 10 degrees Fahrenheit higher than they are today, the sea level was approximately 75 to 120 feet higher than today, there was no permanent sea ice cap in the Arctic and very little ice on Antarctica and Greenland,” said the paper’s lead author, Aradhna Tripati, a UCLA assistant professor in the department of Earth and space sciences and the department of atmospheric and oceanic sciences. “Carbon dioxide is a potent greenhouse gas, and geological observations that we now have for the last 20 million years lend strong support to the idea that carbon dioxide is an important agent for driving climate change throughout Earth’s history,” she said. …