Self-reinforcing feedbacks could push the Earth past the threshold of climate stabilization and into an ongoing path to a “Hothouse Earth”, even if emissions were reduced. That is the conclusion of an international group of 16 scientists published Aug. 6, 2018, in the Proceedings of the National Academy of Science.
“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,” the authors report. “We examine the evidence that such a threshold might exist and where it might be.
“If the threshold is crossed, the resulting trajectory would likely cause serious disruptions to ecosystems, society, and economies. Collective human action is required to steer the Earth System away from a potential threshold and stabilize it in a habitable interglacial-like state. Such action entails stewardship of the entire Earth System—biosphere, climate, and societies—and could include decarbonization of the global economy, enhancement of biosphere carbon sinks, behavioral changes, technological innovations, new governance arrangements, and transformed social values.” See the complete study at http://www.pnas.org/content/early/2018/08/07/1810141115