400ppm: Exit Holocene, Enter Anthropocene July 26, 2013October 13, 2013 Harlan MorehouseUncategorized Written by: Harlan Morehouse on July 26, 2013. Last revised by: admin Excellent forum on climate change, critical geopolitics, and the Anthropocene at EPD’s Society and Space open site. 440ppm @ Society and Space Be Sociable, Share! Tweet