A Post-Carbon Future for Humanity?

The Future of Humanity, Part 7

Image created in PowerPoint by the author.

This is the last post in my modestly titled seven-part series on the future of humanity. The series starts here. Based on all the evidence and analyses we have reviewed in the first six parts, we can now draw some conclusions as to what a post-carbon future for humanity might look like. It won’t be pretty, but my hope is that it might be survivable. Think of the 21st Century as humanity’s biggest, messiest, and most horrible teachable moment. We are either going to learn how to live on this planet … or we’re not.

The graphic above depicts the key dynamics I believe might define the next stage in humanity’s transition to a post-carbon civilization. The curves are purely conceptual, not quantitative, and not on any common scale, except for Time on the x-axis. The logic works something like this:

• Green curve: Fossil fuel reserves will continue to shrink until they are depleted or abandoned sometime in the latter half of the 21st Century (source).
• Blue curve: The decline of fossil fuels will spur technological innovation and investment to find substitutes to replace oil, coal, and natural gas as energy sources, especially in industrial processes that currently rely on them (see Part 3 for examples, also source). These efforts will peak over the next few decades, but decline as fossil fuel shortages become more acute and financial resources become more constrained. The extent to which these efforts will achieve their goals is unknown, but a full-scale replacement of our most complex energy-dependent industries seems unlikely in the limited time available.
• Red curve: Greenhouse gas concentrations in the atmosphere will continue to rise as long as we continue to burn fossil fuels. But as fossil fuels become more scarce, we will burn less, and annual increases in emissions will decline (but overall concentrations will not). Since greenhouse gas emissions drive global warming, average global temperatures will continue to rise along with emissions throughout the century, likely reaching 2–4°C above pre-industrial temperatures by 2100 (source, source). Once fossil fuels are depleted or abandoned, however, temperatures should stop rising, although they will not fall for thousands of years (source). This is the world in which…