The Great Dying wiped out at least 90% of the species on Earth due to an abrupt rise in global-average temperature about 252 million years ago. The vast majority of complex life became extinct.
Based on information from the most conservative sources available, Earth is headed for a similar or higher global-average temperature in the very near future. The recent and near-future rises in temperature are occurring and will occur at least an order of magnitude faster than the worst of all prior mass extinctions.
Habitat for human animals is disappearing throughout the world, and abrupt climate change has barely begun. In the near future, habitat for Homo sapiens will be gone. Shortly thereafter, all humans will die.
This is a printable 62-page version extracted from a detailed and meticulously prepared essay written by Dr. Guy McPherson, Professor Emeritus of Natural Resources and Ecology & Evolutionary Biology, School of Natural Resources and the Environment, University of Arizona. Last updated 2 August 2016.Download Report
The original, complete with several hundred hyperlinked scientific references, can be viewed online here.