The paleoclimate record shouts out to us that, far from being self-stabilizing, the Earth’s climate system is an ornery beast which overreacts even to small nudges.
–Wallace Broecker, climate scientist, 1995
The ongoing Arctic warming corresponds to the predictions of the more pessimistic climate models. By extension, the pessimistic scenarios of climate change can be expected to unfold in the rest of the Northern Hemisphere.
–Louis Fortier, climate scientist, June 2006
We are on the brink of taking the biggest gamble in human history, one that, if we lose, will transform the lives of the next fifty generations….
My focus in this chapter is the question of the century:
Do we humans have the political will to stop the great ice sheets of Greenland and West Antarctica from melting . . . to stop Hell and High Water?
… On our current emissions path, Earth’s average temperature will probably rise 1.5°C by midcentury. By century’s end we will be more than 3°C warmer than today. The last time Earth was 1°C warmer than today, sea levels were 20 feet higher. That occurred during the Eemian interglacial period about 125,000 years ago, when Greenland appears to have had far less ice.
How fast can the sea level rise? Following the last ice age, the world saw sustained melting that raised sea levels more than a foot a decade. Many scientists believe we could see such a melting rate–a catastrophic melting rate of more than 12 inches every ten years– within this century. Sea levels ultimately could rise much more than 20 feet because Antarctica contains far more landlocked ice than Greenland.
The last time Earth was 2° to 3°C warmer than it is now, some 3 million years ago, sea levels were more than 80 feet higher.
… The answer to the question of the century–Do we humans have the political will to stop the great ice sheets from melting?–is, at best, “Not yet”….