Negative Emission Technologies: Our Pathway to a More Hopeful Future?

Carl Sigel

A report issued on October 8, 2018 by the Intergovernmental Panel on Climate Change (IPCC) gave the world a wake-up call. With greenhouse gas (GHG) emissions climbing and climate impacts becoming increasingly more severe, the urgency to address climate change has never been greater. To date the highest priority approach of nations has been to reduce emissions of GHGs by replacing fossil fuels with clean energy sources. Increasing energy efficiency has also been a high priority.

  The latest climate science shows that in addition to reducing emissions, we also need to remove carbon from the air and store it if we are to have a good chance of achieving the global goals of limiting the temperature rise to 1.5 degrees C (2.7 degrees F), the temperature limit, which almost 200 countries agreed to as part of the International Paris Agreement on Climate Change (1).

  Strategies that remove carbon dioxide from the atmosphere are called negative emissions technologies. They are intentional human efforts to remove CO₂ from the atmosphere (1, 2).

  The good news is that we have options and several are based on natural systems (3, 4, 5).  Recent research found that natural solutions like improved management of forests, wetlands, grasslands and engaging in regenerative agricultural can remove about 5.6 gigatons (Gt) CO₂e (6) of carbon per year by 2030.  Natural approaches also carry numerous co-benefits, from improving soil and water quality and increasing food security to protecting biodiversity (3).

  By 2050, the world will need to sequester and store 8 GtCO₂e annually on average—removing more emissions than the total U.S. GHG emissions in 2015 (6.6 GtCO₂e).  Between 2010 and 2100, the world will need to store about 810 GtCO₂ cumulatively, the equivalent of about 20 years of global emissions given current rate (7).

  While results from integrated assessment models show that NETs can play a key role in achieving the 1.5 degrees C goal, there are many challenges to scaling up and deploying them. First, the urgency of the world situation needs to be universally accepted. Second, in general NETs require long periods to put them into practice and third, thousands to millions of people need to be involved in the process on a planetary scale. Lastly, policy frameworks need to be established including incentives for early deployment, niche markets, scale-up, demand, and building public awareness (1).

References and Notes:

1. Sabine Fuss, S., et al, Negative emissions—Part 2: Costs, potentials and side effects 2018, Environ. Res. Lett. 13 063002.
2. Examples of NETs: Marin Carbon Project and Hyde Farm Could Make Duke U Carbon Neutral. Retrieved from https://www.marincarbonproject.org/, and http://www.wunc.org/post/hyde-farm-could-make-duke-u-carbon-neutral, respectively.
3. Minx, J. C. et al., Negative emissions—Part 1: Research landscape and synthesis, 2018, Environ. Res. Lett, 13 063001.
4. Griscom, B. W., et al., Natural Climate Solutions, PNAS, 114, 11645-11650 (2017).
5. Church of the Nativity’s project Becoming the Good Soil, Bearing the Fruit That Will Last was launched two years ago to serve as a catalyst to start and advance carbon farming and composting (NETs).
6. 1 GT (gigaton) = 1 billion metric tons = 1 petagram (Pg) = 10¹⁵g
7. Levin, K, Mulligan, J. and Ellison, G. (March 19, 2018), Taking Greenhouse Gases from the Sky: 7 Things to Know About Carbon Removal, World Resources Institute. Retrieved from (https://www.wri.org.

Picture:

Source: Nancy Bryant, Lazy Heron Farm at 3 Eagles, an organic farm that is using regenerative agricultural approaches in Stanly County, North Carolina.