There are uncertainties about climate science such as tipping points and feedback effects. But these pale in comparison to the biggest source of uncertainties: people. Here are some of the major things we don’t know and really can’t know about future society:
- Will economic growth continue, and if so, how quickly and how uniformly? Richer societies can adapt more easily to climate change, and in a world of high growth we may have less reason for additional investments to aid future generations. Economic models largely assume that the economic growth of the past two centuries will continue for at least the next century or two. But we obviously can’t know this for sure.
- Is the world heading toward a peaceful, democratic future, or one characterized by wars, revolutions, and dictatorships? Our chances of coping with climate disruption (not to mention having high growth) are a lot better in the first scenario. The great human disasters of the last century were due to failures of governance — think of the millions killed in World War II or the Great Leap Forward.
- Will climate change interfere with economic growth or political progress? Will climate change disrupt economic growth? Will climate disruptions cause international instability? Those could be far more costly to society than the physical impacts of climate change.
- Will we choose to decarbonize the global economy? Along with the pathway for economic growth, the extent of our determination to control emissions will determine future atmospheric concentrations of greenhouse gases. That’s a key uncertainty about future climate impacts.
It’s no news that human behavior is hard to predict. That’s just a fact of life. But in the case of climate change, the problem is especially severe because we’re dealing with human nature on a global scale and far into the future. The best-case scenario is one of growing prosperity, peace, and freedom — but we can’t assume that’s the future we’ll actually encounter.