This is the panic post.
Most greatly I fear environmental and biological catastrophe, not just climate change, but also the collapse of crop yields due to disease, the collapse of animal husbandry due to diseases we cannot manage, the collapse of fisheries, the obsolescence of all current antibiotics due to overuse and the emergence of new plagues.
When overpopulation is described in most older Western fiction, the vast growth of cities is the subject. To Robert Heinlein, all the towers of Manhattan were slums, regardless of how happy the residents were. (It's in Tramp Royale, if you want to read the man's own words on the subject.) But long before we feel the crowding, our vast population and use of resources will drive systemic disaster. Randall Munroe recently reminded us that our livestock outweigh us, and that all wild mammals are a tiny fraction of mammalian biomass. If human civilization collapses, from where will come the resources of a wild ecosystem, to rebuild the earth? If the salt shall lose its savor, from where will you resalt it?
And then there is nuclear power. Many scientists, most notably planetologist Jim Hansen, regard nuclear power as a solution to our current energy woes. But I do not believe we are competent to make effective use of it. As with overpopulation the dangers are different than those of the scare stories. It is true that most of the scare stories about nuclear power are wrong: power reactors cannot turn into nuclear bombs, waste can be disposed of if we are willing to undertake the effort and reactors can be designed that will produce fast-decaying radioisotopes that will become harmless in centuries rather than millenia. Yet the land around Chernobyl is so poisoned that even decay takes place more slowly. If we use nuclear power carelessly, over time, it will poison more and more of the earth and, as with fossil fuels, the temptation to misuse nuclear power will always be present. Better, I think, to start now, to reduce our population and develop sustainable non-nuclear energy technology. We would have done best to start decades ago, when the risks became apparent. By the time Al Gore published Earth in the Balance in 1992, it was old news: Gore was summarizing existing results. But we are stuck, and not acting. In some ways we are even making matters worse.
I look for hope from unexpected quarters. When Heinlein wrote Tramp Royale in 1954, he believed that population would continue to grow vastly, and this would lead to resource wars. Instead, contraception became widely accepted, which Heinlein couldn't imagine was possible, and the Green Revolution increased agricultural outputs sufficiently to prevent both these things. We are still not in a good way, but neither have we had global disaster. We may hope for more unexpected good news. Nonetheless we have much hard work before us, if our world and our civilization are to survive.
Books and articles
- Gore, Albert. Earth in the Balance: Ecology and the Human Spirit. Boston, Houghton Mifflin, 1992.
- Heinlein, Robert A., Tramp Royale. Baen Books, 1996, ebook. (Original completion date 1954. If you're tempted to read this, be warned that that the book and Heinlein's prejudices have aged badly.)
- Munroe, Randall, "xkcd 1338: Land Mammals," self-published web comic.
- Nuwer, R., Forests Around Chernobyl Aren’t Decaying Properly. Smithsonian Magazine, March 2014.