Part 1: 6 Ways We’re Pulling Carbon from the Air — What I Learned from AirMiners BootUp

Why does carbon dioxide removal (CDR) matter? 

Whether you’re new to the CDR space or you’ve been here for a long time, it’s important to have a high level understanding of each methodology that exists to fight the ever increasing effects of climate change. I recently completed the AirMiners Bootup course. If you’re interested in expanding your knowledge of CDR, the next cohort begins on November 11 (https://bootup.airminers.com/). 

There are six main categories of CDR. Over the next few weeks, I’ll share deeper takeaways on what I’ve learned and how these methods intersect with science, policy, and community needs. The following is a preview:

• Soil Organic Carbon: Soil holds more carbon than all plants and the atmosphere combined. By implementing agricultural land management practices such as reduced tillage, organic amendments, and cover cropping, carbon storage potential can increase even more, creating a powerful climate change mitigation tool.

• Forests Carbon Removal: Trees are the world’s lungs. Roughly 16% of the USA’s CO2 emissions are captured from forests covering ⅓ of the nation. Afforestation, Reforestation, and Revegetation (ARR) projects tend to be the most effective at capturing atmospheric CO2 since growing trees take in more carbon than mature trees. 

• Biomass: Agricultural and organic waste can be transformed into long-lived products or buried for durable storage. Biochar is the most widespread today, but there’s a trade-off between accessibility vs. permanence. 

• Direct Air Capture: We have the technology to remove CO2 directly from the air, but this requires a large amount of heat and energy. Some companies have chosen to co-locate their DAC facilities near geothermal hotspots, allowing the facilities to piggyback off of earth’s natural heat source instead of using oil and gas. 

• Carbon Mineralization: There are three main avenues: 

  • Geosequestration –  stores highly pure CO2 in geologically stable rock within earth’s crust.

  • Mineral storage –  uses a redactor to transform gaseous CO2 into a solid mineral form that can be used as building materials such as concrete or road bases.

  • Basaltic Enhanced Rock Weathering (ERW) –  focuses on expediting naturally occurring geochemistry to capture CO2. 

• Biotic Ocean CDR: Blue carbon ecosystems such as mangroves and seagrass meadows are highly effective at sequestering carbon into coastal soil. However, these projects can take up to 17 years for maximum carbon sequestration potentials. Community member involvement is critical for the overall success and longevity of these projects. 

• Abiotic Ocean CDR: 90% of the world’s excess heat and 25% of the excess CO2 emissions are absorbed by the ocean. This has pushed the biochemical equilibrium towards a hotter, more acidic ocean. Ocean Alkalinity Enhancement (OAE) pushes back by utilizing natural alkaline minerals like olivine to release silica, magnesium, and other trace metals. Additional real-world testing needs to be conducted before large-scale implementation can be implemented. 

Reflection

There is no single silver bullet to mitigating the effects of climate change. However, a diverse portfolio of CDR methods can strengthen our climate response for an effective push forward. Technology and innovation continue to advance at rapid speeds, making it ever more important to align science, policy, and community from the start. 

Question to you

Which CDR pathway do you think has the highest scalable potential? Which one keeps you up at night? 

Follow along for a deeper dive into Soil Carbon next week.