For decades, scientists have agreed that minimizing the release of anthropogenic (human-made) greenhouse gas emissions is paramount to mitigating the potential impacts of climate change. Since the beginning of the Industrial Era, humans have released greenhouse gases into the atmosphere, primarily through the burning of fossil fuels. Greenhouse gases prevent heat from escaping earth’s atmosphere, thereby amplifying raising earth’s temperature through “the greenhouse effect.” However, emission reductions, while hindering climate change development, aren’t enough to address the threat of committed warming. Indeed, according to a study conducted by MIT, given that 80% of carbon dioxide emissions leave the atmosphere “on a scale of centuries to millennia,” even if anthropogenic emissions completely ceased, outgoing longwave radiation from earth’s surface would continue to be trapped by the greenhouse gases which have already been emitted. This committed warming may not threaten generations in the very near future, but it is certain to impact humanity for centuries to come.
To return atmospheric CO2 concentrations to pre-industrial levels without relying on carbon cycle redistribution, climate change scientists have worked to develop the field of Carbon Sequestration and Storage (CSS). CSS is a two step process in which CO2 emissions are captured from the atmosphere and then stored elsewhere, directly reducing the atmospheric concentration of CO2. Generally, the captured CO2 is compressed into a liquid-like state and transported through an underground pipeline to a storage site, with the most common long-term storage archetype being geologic formations thousands of feet underground. As for the means of capture, methods vary widely, with the CO2 capture component being more expensive and technically difficult than CO2 storage. Two of the most common carbon sequestration methods include constructing forests, since trees serve as natural capture sequestration devices, and creating chemicals specially designed to capture CO2 from the open air. Of the two methods, chemical design bears notable potential, since a reusable, cheaply made, and reasonably efficient product would far outpace the slower method of tree cultivation.
The latest new edition to the CSS industry, the chemical COF-999, created by reticular chemist Omar Yaghi, the senior officer of the COF-999 study at UC Berkeley, exhibits all of these properties. Described by Klaus Lackner, director of the Center for Negative Carbon Emissions, as “opening a door into a new family of approaches,” COF-999 appears to be the most commercializable CSS chemical to date, by far.
COF-999 is in a class of molecules called a covalent organic framework (COF) and has a porous, crystalline structure modified by polyamines. A COF structure is akin to the covalent network structure of a diamond, with strong covalent bonds connecting each layer of the molecule; however, the stacked layers are hollow in the middle, prompting study leader Zihui Zhou to describe COF-999 as “tiny basketballs with billions of holes.” The polyamine addition, due to the specifications of its minor alkalinity, is the mechanism which attracts the CO2, while the porosity of the COF structure ensures ample storage space. After being heated, the molecule expands and its porous holes loosen, releasing the captured CO2 for storage.
COF-999 outdoes its competitors on many key fronts. It captures CO2 at a rate “at least 10 times faster” than other carbon capture chemicals, and it releases the captured CO2 once heated to 60℃, compared to the 121℃ required of other molecules. Although Yaghi reports that COF-999 “doesn’t require any expensive or exotic materials,” Lackner notes that the CSS process must become “10 times cheaper than it is now” before it can meaningfully aid in reducing the atmospheric carbon dioxide concentration, suggesting that scientists will need to develop more cost-effective methods in future COF-999 renditions. Nonetheless, COF-999 appears to be on the cutting edge of CSS technologies and is therefore a key indicator of the field’s future direction.
However, despite COF-999’s many exciting results, a potential key issue with Yaghi’s project may serve as a cautionary tale, highlighting the challenges of pursuing CSS research at this stage in humanity’s fight against climate change. The COF-999 project has been funded by three sources: Yaghi’s own Atoco, the Bakar Institute of Digital Materials for the Planet, and the King Abdulaziz City for Science and Technology (KACST). While the Bakar Institute seeks the invention of ground breaking, if not miraculous technology to address the climate crisis in its own right, KACST, although certainly reputable, is a government agency within Saudi Arabia, a country which currently holds the second largest supply of known oil reserves in the world and relies on oil and gas production for half of its GDP. Additionally, despite pledging to derive 50% of its electricity from renewables by 2030, the country derived less than 2% of its electricity from renewables in 2022. Altogether, it is evident that Saudi Arabia has not only failed to prioritize CO2 emissions reductions, but is also significantly economically de-incentivized from beginning reductions so long as its economy continues to rely on them. While America, the American Bakar Institute, and American oil and gas companies undoubtedly have their own incentives to discourage emissions reductions, Saudi Arabia, perhaps more so than other countries, would prefer a solution to the climate crisis besides cutting back on emissions. Their funding of a breakthrough CSS technology, an ideal means towards this end, epitomizes the fantasy that reducing greenhouse gas emissions is not an inevitable step towards ending the climate crisis.
While some may argue that all funding towards climate solutions is good funding, the damage that will be caused to communities and the environment as a result of emissions cannot be addressed by CSS alone. CSS may reach a point in development where it can help reduce emissions to pre-industrial levels, thereby preventing continued increases of greenhouse gas emissions, but the warming that occurs before this point cannot be undone by CSS technology. To rapidly counteract committed warming, a Solar Radiation Management (SRM) strategy would likely have to be employed, an industry which, like CSS, has yet to develop any reliable, scalable solutions. As for decreasing carbon dioxide emissions past pre-individual levels with CSS, thereby anthropogenically cooling the planet, the resulting positive feedback loops may cool the planet beyond intention.
Considering CSS investment as a climate strategy that can replace emissions reductions would enable nations benefiting from the fossil fuel industry to continue emitting greenhouse gases while relying on CSS technology to bail them out. However, such investment may ultimately prove insufficient to reverse anthropogenic emissions—and even if it does succeed, it will not address the realized and continued impacts of prior warming. The case of COF-999 demonstrates that while humanity cannot rely entirely on emissions reductions to address the climate crisis, it also cannot rely entirely on CSS. Neither can it allow nations with vested fossil fuel interests to justify continued emissions by pointing to their support for CSS research as a substitute for meaningful climate action.