One of the unfortunate truths of the climate crisis we’re in is that when we finally stop making things worse, it won’t suddenly make things better. The carbon dioxide we’ve put into the atmosphere and the oceans will persist for hundreds, even thousands of years; temperatures will remain high; many ecosystems will be permanently disrupted; and species driven to extinction—well, they’ll still be extinct. The eventual return to a planetary equilibrium won’t happen on anything approaching a human timescale.
This isn’t a story we like to hear. The heroic narrative of fighting global warming implies that victory will mean getting back the Earth we know and love. But the reality of the situation is that significant damage has already been done; putting a stop to carbon emissions still leaves us with a planetary mess.
It’s useful to consider the alternatives we’ll have when the time comes to start the cleanup. It may seem premature to be talking about what to do after we’ve put an end to using the atmosphere and ocean as a carbon dump, but it’s often useful to consider one’s eventual destination even when still trying to figure out the map. When that time comes, we’ll face a choice between trying to accelerate the return to the equilibrium the world has known for millennia, trying to adapt ourselves and our environment to the new normal, or simply adapting ourselves and letting the new environmental conditions evolve on their own. It’s a sobering set of options.
Accelerating the return to equilibrium would mean, at a minimum, direct intervention to reduce atmospheric and oceanic carbon loads; it would also likely require some effort to moderate temperatures at a planetary scale (aka geoengineering). A true return to equilibrium would come to depend on programs such as Stewart Brand and Ryan Phelan’s proposal to revive extinct species, and would necessitate extraordinary research into the nature of re-creating ecosystems, including everything from pollinating insects to soil microbes. It would be a massive undertaking and, to be clear, would not result in a return to pre-Anthropocene (or even pre-Industrial Age) conditions—too many species have been lost, and too many ecosystem changes are irreversible. Call this the “(Re)Terraforming” future—using every tool at our disposal to make the Earth Earth-like again.
None of these scenarios should sound especially appealing. We left the appealing scenarios behind decades ago.
Less ambitious (in comparison, at least) would be to attempt large-scale adaptation of environmental and human systems to high-temperature conditions. This would mean reimagining the nature of cities and buildings, a transformation of the typical diet and—most profoundly—the genetic manipulation of many plants and animals to better withstand higher temperatures and persistent drought. Any reintroduction of extinct or near-extinct plants and animals would demand close scrutiny of ecological requirements and genetic options; it’s likely we’d see large-scale experiments in the creation of novel, even unprecedented, ecosystems. We could call this one the “Anthropoforming” future—using our tools to make the Anthropocene easier to survive.
Finally, there’s the hands-off approach, sometimes called “re-wilding.” Human adaptation would take place in ways that parallel the previous scenario, but natural ecosystems are left to themselves. Certainly, permitting the return of the wild by pulling back the boundaries of civilization has some visceral appeal. It’s letting nature take over again, and puts explicit limits on the human footprint. What often goes unsaid, however, is that the new wild would bear little resemblance to what had been there previously; with the impacts of changing temperatures and corresponding ecosystem disruption, we’re more likely to see the quick dominance of opportunistic, invasive species. We’d call this the “Hands-Off” future, although re-wilding through abandonment might also be thought of as the “rats and kudzu” future.
Thinking now about these options would let us focus our research accordingly. Do we undertake extensive study of how ecosystems operate, and what can be done to create them? Do we attempt a planet-wide genome map as the first step in adaptive modification? Or do we focus our attention on human adaptation to a world with greatly constrained resources and minimally diverse ecosystems?
None of these scenarios should sound especially appealing. We left the appealing scenarios behind decades ago. But these three do sketch out the possibilities that await us. Getting control of global carbon emissions isn’t the end of the story—it’s just the beginning of the next chapter.