Clive Hamilton (Australian climate economist and Professor of Public Ethics at the Centre for Applied Philosophy and Public Ethics (CAPPE) and the Vice-Chancellor's Chair in Public Ethics at Charles Sturt University) on human survival in “The Four Degrees World” (2010): “One way or another, humans will have to adapt to life in a hotter world. Many plausible scenarios suggest a sharp decline in the number of people that will survive in the long term. Some suggest a billion or a few hundred million will remain in a century or two, but one guess is as good as another. One thing is certain: the transition to a new stage of stability will be long and brutal, especially for the poorest and most vulnerable whose survival will be threatened with food shortages, extreme weather events and diseased” [1].
[1]. Clive Hamilton, page 204, “The Four Degree World”, Chapter 7 in “Requiem for a Species. Why we resist the truth about climate change”, Allen & Unwin, 2010.