One does not need to be a climate scientist to work out that, in spite of government rhetoric to the contrary, there is absolutely no real movement in the direction of global emission reduction at the scale needed. That means in all likelihood we are headed toward a catastrophe that could easily pushed modern civilization to a breaking point.
By exploring possible parameters here, I hope to encourage more thinking and discussion about measures that might make sense as insurance against complete climate upheaval and the collapse of global civilization. In other words, the kind of thing we expect could happen with 5° or 6° C. warming—a worse case scenario so to speak. What would provide us with a “fallback plan” to preserve what we consider most valuable in our civilization should we fail to prevent dangerous levels of global warming?
What does a 5-6°C average global temperature increase really mean for humanity?
To answer that question, British author and journalist Mark Lynas spent 3 years of his life poring over 10,000 scientific papers and found that, although it doesn’t sound like a lot, a 5ºC or 6ºC temperature would be devastating.
The National Geographic documentary based on Lynas’ work describes how at 5ºC, two massive uninhabitable zones wouldspread into once temperate regions of Northern and Southern hemispheres. The snow packs and aquifers that feed the great cities would dry up. And climate refuges would number in the hundreds of millions. “I think in a world that is much warmer than now, 5ºC, it is going to be inconceivable that human civilization can withstand that kind of climatic shock,” said Lynas.
At 5ºC, suggested National Geographic, we in essence enter the twilight zone of climate change, a nightmare vision of life on Earth where traditional social systems break down.
With between 4°-5 ° C. warming, Earth becomes an entirely different planet, noted environmental journalist Richard Girling in the Sunday Times after interviewing Lynas. Ice sheets would vanished from both poles; rain forests would burn up and turn to desert; rising seas would scour deep into continental interiors. Populations would probably try to move from arid areas to the newly thawed regions of the far north, in Canada and Siberia. Of course, there is no guarantee that northern governments would willingly admit southern refugees, so Siberia and Canada could easily end up being invaded by China and the US militaries.
And even if southern governments don’t invade the north, certainly migrants would attempt to force their way into remaining habitable enclaves in a fight for survival.
Where no refuge is available, civil war and a collapse into racial or communal conflict seems the likely outcome. Isolated survivalism, however, may be as impracticable as dialing for room service, suggests Girling. How many of us could really trap or kill enough game to feed a family? Even if large numbers of people did successfully manage to fan out into the countryside, wildlife populations would quickly dwindle under the pressure. Supporting a hunter-gatherer lifestyle takes 10 to 100 times the land per person that a settled agricultural community needs.

A large-scale resort to survivalism would turn into a further disaster for biodiversity as hungry humans killed and ate anything that moved. Including, perhaps, each other. Invaders do not take kindly to residents denying them food. History suggests that if a stockpile is discovered, the householder and his family may be tortured and killed. Look for comparison to the experience of present-day Somalia, Sudan or Burundi, where conflicts over scarce land and food are at the root of lingering tribal wars and state collapse.
James Lovelock points out that extreme temperatures don’t necessarily mean that there are not areas when people could still live on the planet. The Arctic might again become tropical, as it was in the past, but it would probably be habitable, for instance. After years of being one of the environmental movement’s most influential figures (according to one British newspaper), in the face of an honest assessment of future climate impacts, he finally concluded that our best strategy might be not sustainable development, but rather sustainable retreat.
“We suspect that we have little time left to deal with climate change, overpopulation, food and water shortage, and other adverse consequences of our accelerated way of living,” wrote Lovelock. “But how do we choose between the remedies on offer? Do we try sustainable development and renewed energy? Or do we bite the atom and rely on nuclear energy? Some offer to geoengineer the Earth to an ideal composition and climate. I think we might do worse than have trust in Gaia to regulate the Earth as she has done since life began, and retreat to the best [cooled] cities that we can design and build with the objective of saving as many of us as we can; and entirely abandon the absurdly hubristic idea of saving the planet.”
Climate Conflicts
As our climate heats up, the risk of war increases. And of course, that includes the risk of nuclear war.
Syria is one good example. A recent study published in the U.S. Proceedings of the National Academy of Sciences details how the drought in Syria, exacerbated to record levels by global warming, pushed social unrest in that nation into an open uprising in 2011. And subsequently, this conflict became a major civil war with international involvement.

It’s not hard to see why this can happen. The drought in Syria from 2006 to 2011— the worst on record there —destroyed agriculture, causing many farm families to migrate to cities. This influx added to social stresses already created by refugees pouring in from the war in Iraq. And the drought also pushed up food prices, aggravating poverty.
“We’re not saying the drought caused the war,” Richard Seager, a climate scientist at Columbia University’s Lamont-Doherty Earth Observatory who co-authored the study, told Scientific American. “We’re saying that added to all the other stressors, it helped kick things over the threshold into open conflict. And a drought of that severity was made much more likely by the ongoing human-driven drying of that region.”
The Syrian situation is far from unique. According to the U.S. Department of Defense, climate change is now regarded as a “threat multiplier” that can exacerbate other problems. Droughts and other climate-related resource scarcity can intensify conflicts over resources, for example.
Ex-C.I.A. analyst Paul R. Pillar goes so far as to argue that climate change as a “threat multiplier” could not only put the world on course toward worsening chaos, but even extermination as nuclear-armed nations scramble to cope with environmental dislocations and resource shortages.
In other words, as the impacts of climate change become more catastrophic, these exacerbate other problems and so increase the risk of nuclear war.
One troubling thought is that as we start moving to temperature and weather extremes, with increasing droughts and floods, nuclear war might be seen in some warped way as a solution to over-population. In theory at least, significantly reducing the Earth’s population could also significantly reduce our greenhouse gas output. More and more, we are starting to hear that true planetary sustainability may only be possible if we reduced Earth’s population below 500 million.
CNN founder Ted Turner, for example, has argued, “A total population of 250-300 million people, a 95% decline from present levels, would be ideal.” Dave Foreman, the co-founder of Earth First, says that reducing our population down to 100 million is one of his goals.
Mikhail Gorbachev, who focused on environmental issues by founding the Green Cross International after stepping down from Soviet leadership, argues that the ecological crisis is really a population crisis. “Cut the population by 90% and there aren’t enough people left to do a great deal of ecological damage,” he has said.
Not that any of the people who have suggested that we need an extreme population reduction would ever contemplate measures like a thermonuclear war to achieve it. But who is to say that some future government leader with a finger is on the nuclear trigger won’t consider this? It is an unnerving, morbid thought, but we shouldn’t forget that psychopaths like Hitler do occasionally rise to the pinnacles of political power.”