Hothouse Earth: Crossing the threshold would lead to a much higher global average temperature than any interglacial in the past 1.2 million years and to sea levels significantly higher than at any time in the Holocene pnas.org Submitted by BigG on December 6, 2018 at 9:54 AM in collapse (edited on December 6, 2018 at 9:55 AM) No comments 3