From the WSJ's Morning Brief:
"The last time it was that warm was in the middle Pliocene, about three million years ago, when sea levels were estimated to have been 25 meters (80 feet) higher than today," James Hansen, head of NASA's Goddard Institute for Space Studies, tells The Wall Street Journal, after the agency warned the Earth's temperature is rising at an accelerating pace with readings that imply we are getting close to "dangerous" levels of human pollution.
