Examples of NETs include nature-based solutions such as afforestation, reforestation, and the use of agricultural soils that can take up and store carbon; of the various proposals made to date, these technologies are included in a short list of NETs that are sufficiently developed to remove carbon from the atmosphere for less than $100 per tonne.⁸ Unfortunately, these technologies also require rapid and widespread changes in forest and soil management practices. Unfortunately, many past programs, meant to provoke landowners to change their behaviour, have been unsuccessful. So, transforming how society manages its land is no small challenge. Given this, other proposals regarding NETs have been made. These include activities such as extracting CO₂ directly from the atmosphere using chemical interactions, a process called direct air capture (DAC). In this case, the CO₂ would be extracted from air and subsequently sequestered underground for long term storage.⁹ Unfortunately, DAC is still in its early stages, making it too expensive at the moment. Like other NETs, DAC also must be combined with a robust carbon-pricing system, which mandates that emitters pay for the greenhouse gases that they produce as a cost for “clean up”. Such carbon pricing is key, as it can help pay for the capture process and promote NET optimisation; the latter can reduce the economic cost associated with removing carbon from the atmosphere, and hence, help to eventually develop a CO₂ market that might further incentivise the adoption of NETs.

Image credit: Climeworks direct air capture plant to sky image is © Climework, by Julia Dunlop