Proposed approaches vary widely, but all share a few key features: they are technologically uncertain, environmentally risky, and more likely to accelerate the climate crisis than to reverse it.
As concentrations of atmospheric carbon dioxide surpass 400 parts per million, the costs of the climate crisis—in terms of economic losses, environmental impacts, and human lives—continue to rise. Last October, the Intergovernmental Panel on Climate Change (IPCC) warned that global temperatures approaching 1.5°C above pre-industrial levels will have serious consequences for humanity and biodiversity. Anything beyond that level will be catastrophic.
To avoid crossing the 1.5°C threshold, the world must nearly halve its CO2 emissions by 2030, and reach net zero emissions by 2050. This will be possible only if we completely eliminate fossil fuels from the economy within the next few decades. Attempts to circumvent that reality will only make matters worse.
We’re at risk of doing just that. A growing number of people are now considering the once-unthinkable strategy of geoengineering our way out of the climate crisis. Proposed approaches vary widely, but all share a few key features: they are technologically uncertain, environmentally risky, and more likely to accelerate the climate crisis than to reverse it.
Proponents advocate two main geoengineering strategies: carbon dioxide removal (CDR) and solar radiation modification (SRM). Both – along with most other geoengineering strategies—would depend on the widespread deployment of so-called carbon capture, utilization, and storage (CCUS), in which a suite of technologies captures CO2 from industrial waste streams and stores it underground, in the oceans, or in materials.
On its own, this would raise serious environmental and social risks. But, economically, CCUS is viable only if captured carbon is pumped into old oil wells to force out more oil, into abandoned coal mines to produce natural gas, or into refineries to produce yet more plastic. This would benefit the fossil-fuel industry—and hurt everyone else.
The specifics of each strategy only reinforce the dangers of geoengineering. Consider CDR, which aims to absorb carbon from the atmosphere after it has been emitted. The most widely discussed approach—bioenergy with carbon capture and storage (BECCS)—would mean clearing large stretches of intact forest, displacing food crops, or both, to produce more burnable fuels. This would not only threaten food security and land rights; the clearing of forests could cause more carbon to be released than BECCS ever absorbs.
Another major CDR technology—direct air capture (DAC)—would suck CO2 from the air by installing what are essentially huge air filters around the planet. To pay for this extremely energy-intensive process, proponents want to use the captured CO2 to produce diesel and jet fuels, which would then be burned and re-emitted in an endless cycle. Put simply, DAC is a very expensive means of turning renewable energy into gas.
Bioenergy with carbon capture and storage would mean clearing large stretches of intact forest, displacing food crops, or both, to produce more burnable fuels.
The other major geoengineering strategy, SRM, seeks to mask rather than reduce atmospheric CO2. The most widely discussed approach involves injecting sulfur dioxide (SO2) into the upper atmosphere, producing a temporary cooling effect.
But burning coal, oil, and gas—which also produce large amounts of SO2—has the same effect, while also causing acid rain and depleting the ozone layer. Proponents of SRM thus argue, perversely, that we should protect the planet by producing more of the pollutants that are already destroying it.
The explanation for this apparent cognitive dissonance is simple. As a new analysis by the Center for International Environmental Law shows, many of those advocating geoengineering have worked for, been funded by, or stood to profit from the fossil-fuel industries that created the climate crisis in the first place.
The oil, gas, coal, and utility industries have spent decades researching, patenting, and promoting geoengineering technologies—including, for example, CCUS—with the goal of safeguarding the dominant role of fossil fuels in the economy. And our research shows that the primary effects of geoengineering would be to entrench that role further, contribute to increased CO2 emissions, and lock in fossil-fuel infrastructure for decades or even centuries to come.
This is clearly a counter-productive strategy for addressing the climate crisis. But that does not matter to geoengineering boosters, many of whom—including the American Enterprise Institute, US Representative Lamar Smith, and former US Secretary of State (and ExxonMobil CEO) Rex Tillerson—are climate-change deniers who oppose mitigation policies. If global warming ever does become a real problem, they argue, we will just geoengineer our way out of it.
But what is expedient for vested fossil-fuel interests is out of line with reality. The cold truth is that we have less than a decade to reduce CO2emissions dramatically, and less than three decades to eliminate them entirely. The world simply cannot afford to waste any more time and resources on geoengineering myths and fantasies.
We have the tools we need to tackle the climate crisis. Promoting renewable energy and energy efficiency, protecting and restoring natural forests and ocean ecosystems, and respecting the right of indigenous peoples to act as stewards of their traditional lands are all workable, cost-effective solutions to the climate crisis that can be deployed and scaled up now. All that is needed is the political will to embrace them – and the will to reject specious strategies devised by those who should be fixing the problem, rather than dreaming up new ways to profit from it.