There was a time when humans could impact genes only crudely, such as through radiation. Nowadays, thanks to gene-editing technologies, particularly CRISPR-CAS9, we can edit genes accurately.
Global warming will unleash frequent disasters like hurricanes and flooding. The largely human source of this mess shows that we can impact the climate. So far, that impact remains largely adverse. In the future, we may also develop crude tools for intentional positive impact on the climate.
Sufficiently powered for substantial impact, however, standard geoengineering interventions, such as reflecting a small percentage of the sun’s energy back into space with the intent to curb overall global warming, are likely to produce many negative side effects. Like substantial changes to monsoons, for one.
Just as radiation can be worth it overall when it protects patients from bad cancers, standard geoengineering may be worth it overall—but it is suboptimal.
More precise tools for altering local weather are also in existence, cloud seeding can be used to augment local precipitation (some forms are safe; efficacy is debated) and, on a tiny scale, your AC’s “climate control.” Think of these tools as “precision geoengineering.” Each intervention individually avoids major negative externalities, but its positive impact on the climate system is minor. And cumulatively, they may have substantial net negative effects: taken together, the world’s air conditioning units make the planet much warmer.
Imagine, however, “climate editing”— a potential massive future network of precise, local, and mutually-coordinated interventions. In concert, they would harness prior knowledge on what affects the environment and how to “edit” the climate favorably. Many of these interventions would be tasked to address the foreseen side effects of others. These “edits” would carry out a detailed plan, with real-time monitoring and course-corrections.
Ideally, such coordinated interventions would foil some climate disasters, or facilitate long-term climate improvements, with relative safety. They may carry fewer negative, unmanageable consequences than either business as usual or crude geoengineering or uncoordinated local interventions. Why? Because coordination across the system would avoid or compensate for some negative externalities.
If things work out ideally, climate editing would be highly desirable. It would save us from some environmental woes, at comparatively modest sacrifice.
But successful climate editing may turn out to be an impossibility, not just in the near term, but in the far future. It would be impossible so long as any of the following bottlenecks remains in place:
- We lack the technology to affect the climate in all the necessary ways;
- We cannot predict well enough the impact of these technologies;
- We cannot fund and govern peacefully and over time the massive network of mutually-dependent interventions across geopolitical zones.
Can sufficient general scientific advancement teach us how to overcome all of these bottlenecks? The challenges may seem overwhelming.
First, the climate is subject to many more forms of influence than our genome, making prediction of climate edits’ effects on the climate elusive. But that may mean only that in order to climate-edit successfully, we need to know much more than we currently do, not that we could never do it. In gene editing, what seemed impossible in one era became a reality in another (plus, the epigenome is subject to many forms of influence).
Another challenge is that the tools of climate editing may introduce environmental problems, just as gene editing may cause new mutations. Nonetheless, new tools may also emerge to preempt or to resolve these environmental problems.
A third challenge is the chaotic nature of the climate system, which would limit ability to predict satisfactorily the impact of technological interventions even once more is known.
These and other challenges to successful climate editing might turn out to be tractable. For many centuries, rainmaking was the material of prayers and witchcraft, yet intentional cloud seeding has now been in wide use for decades. If all identifiable challenges are resolvable, research and advocacy toward future climate editing would warrant considerable investment.
* Thanks to Mark Budolfson, Marc Lipsitch, Leah Price, and Shelly Simana for helpful comments.