Future Climate Projections

Abstract

The Anthropocene event constitutes a unique period distinct from previous global warming events. Following on stadial cooling intervals, including the Younger dryas (12.9–11.7 Ma) and the Laurentian stadial (~8.2 kyr), consequent on flow of cold ice-melt water into the Atlantic Ocean. Gradual cooling of the Holocene, with minor interruptions, gave way to the extreme warming of the Anthropocene. Palaeoclimate-based projections suggest an interglacial period over 10,000 year-long,  projected to last another 50,000 years under atmospheric greenhouse conditions (Berger and Loutre, Science 297:1287–1288, 2002), significantly longer than the Eemian, which lasted for about 10,000 years. Whereas the gradual cooling since the peak Holocene 6000 years ago was projected to lead to a cold interval from about 25,000 years in the future and to glaciation in about 55,000 years in the future, the massive injection of greenhouse gases during the late Anthropocene heralds an extension of the Holocene interglacial to the length of Marine Isotope Stage-11 of ~50,000 years and longer. Climate simulations for the next 100,000 years, as a function of insolation and CO₂ variations, lead to an exceptionally long interglacial ahead.