The end point as Dyer sees it, would be a total human population in the millions clustered around the Arctic Ocean. Everyone else will be dead either by famine or war or disease within one or two hundred years.
Dyer doesn't think that this is inevitable, however, because he thinks that there are "on the shelf" geo-engineering solutions that will allow the human race the "breathing room" necessary to develop solutions to the greenhouse problem. These include things like spraying the stratosphere with sulfur dioxide, creating fleets of wind-powered robot ships that spray water into the air, building giant space mirrors to shade earth, etc. The idea is that these techno-fixes would reflect enough sunlight that they would keep the planet from heating up to a dangerous level.
What I'm interested about with regard to all of this is my personal reaction to Gwynne's dire predictions. I have devoted enormous amounts of time and energy in the battle to prevent global climate change. Primarily, this was based on a real terror of what could happen. As it happens around me, I've had to think deeply about the nature of that fear.
Oddly enough, I've come to the conclusion that it is fundamentally misplaced.
It seems horrible to consider the vast majority of the human race dying off in some sort of environmental cataclysm. But the fact of the matter is that every single person who has been born has died in one way or another. And most of the ways that people do die are pretty bad. Ultimately, what real difference is there between starving to death in just another run-of-the-mill famine or the "mother of all famines" caused by climate change? Or dying in an ordinary war caused by sheer stupidity instead of one caused by societies that are on the verge of collapse due to environmental catastrophe? Again, what is the difference between dying of cholera because your society hasn't really figured out how to give working people clean water versus getting something bad because your society has collapsed? Either way, in all of these cases, you end up dead. And I suspect that if you look at mortuary statistics the overwhelming majority of people in any age have died due to hunger, violence or disease.
So what would be all that new in Dyer's scenario?
Not much, really. There is the death of nature, but I don't think that I'd be being really honest if I said that that was the source of my extreme emotions. Instead, I think that a larger fraction of my concern is my own fear of personal extinction. Indeed, in a real sense the entire world "ends" when every one of expires---at least for the individual in question. Perhaps contemplating the death of nature (or, to me more precise, its radical change) forces me to direct my gaze in ways that I prefer not.