The report, published in early October by the Intergovernmental Panel on Climate Change (IPCC), a branch spearheaded by the United Nations, says it all: Earth is hard set on a trajectory towards climate disaster, and it is all due to greenhouse gas emissions. According to the IPCC’s global panel of 91 authors and review editors, continuing at our current rate of warming means we could very well reach the 1.5 degrees Celsius threshold (measured against the 19th century baseline) by 2030. This means immense loss of sea ice during the summer, extreme heat afflicting 14% of the population, sea level rises targeting 31 to 69 million people, water scarcity and drought, species loss – especially coral reef mortality, and losses across the world in crop yield. Half a degree is incredibly dangerous, and all of this would be compounded at even greater temperatures; it is highly likely we will see 2 to even 3 degrees by the end of the century, if no action is taken.
To rein in warming at 1.5 degrees, the report said, we need to cut our greenhouse gas emissions in half within 12 years and go virtually carbon neutral by 2050. The news was shocking. In the short time we have, essentially all carbon dioxide fuel dependents need to be phased out by renewable energy. Furthermore, negative emissions technologies have to annually remove billions of tons of carbon dioxide from the atmosphere. According to the U.S. Geological Survey (USGS), “sequestration and reduction of emissions over the next two to three decades will potentially have a substantial impact on long term opportunities to stabilize levels of atmospheric CO2 and mitigate impacts of climate change.” This is the piece of the puzzle, that, if located quickly enough and fit into its role, could be a game-changer, slowing down the clock.
Negative emissions entail the use of carbon sequestration, the “natural and deliberate processes by which CO2 is either removed from the atmosphere or diverted from emission sources and stored in the ocean, terrestrial environments (vegetation, soils, and sediment), and geologic formations.” This may be employed through low-tech policies like afforestation and reforestation, “carbon farming” via planting longer-rooted crops and adding in organic reagents to capture carbon in soil, encouraging regrowth of coastal plants – especially mangroves – to store carbon and protect eroding shorelines, and crushing naturally absorbent silicate rocks to chemically bond with atmospheric CO2. These are readily accomplished with the tools we already have, just in need of time and space. Contrast this with other high output technology that has only recently emerged from the lab.
Towards this more experimental but greater impact range, techniques like BECCS, or bioenergy carbon capture and storage, may be of value. BECCS is the process of using biomass as fuel and diverting the carbon dioxide product to storage deep beneath the ground or for use in industrial products like concrete or plastic. In order to store the gas in rock formations, it must first be compressed into fluid and then funneled through pipelines to reach porous rock, typically a mile or more underground, that is layered over by an impermeable rock shelf. Researchers at the Lawrence Berkeley National Laboratory at the University of California, Berkeley, for instance, have developed a way to convert carbon dioxide into carbon monoxide through “porous, crystalline covalent organic frameworks,” which can then be used in fuel, plastics, or pharmaceuticals.
Another promising but still emerging technology is direct air capture and storage (DAC), whereby CO2 is captured from the atmosphere and then channeled deep underground, as in BECCS. The Switzerland-based Climeworks has engineered the “first commercial carbon removal technology today,” allowing other companies to begin cleaning up their footprint. In Iceland, the CarbFix project has allowed the Hellisheidi geothermal plant to become carbon negative, as any carbon dioxide byproducts are injected underground and then rapidly mineralized.
The lasting problem with any carbon sequestration method is the time frame. Time is required to either thoroughly bring more theoretical projects to application on a grand scale, or to allow any major effect take place at all; that is, they lack efficiency. Our best bet may be on a composite of all of these techniques, each of them carving out their own section of global emissions. “A roadmap for rapid decarbonization” has been laid out for us, necessitating the sequestration of 0.61 metric gigatons annually by 2030, 5.51 by 2050, and 17.72 by 2100. Considering that afforestation, reforestation, carbon farming, and crushed rock may contribute up to 14-18 gigatons of stored carbon each, this projection is feasible; it just needs to be put into motion.
While carbon sequestration is a necessary innovation, we need additionally and perhaps more pressingly to focus on bringing renewable energy to the forefront. This can be done through encouraging its presence in the market and affixing a much needed carbon tax, so that corporations – the main perpetrators of our century long carbon siege – will be punished for their pollution, which currently goes largely unchecked. Ideally, with renewables working in conjunction with carbon sequestration, and with the mindset of acting quickly in the next few years, we can finally put a hold on greenhouse gas escalation.