The Urgency of Scalable Carbon Removal by 2050

The Urgency of Scalable Carbon Removal by 2050
by Simon Mansfield
Sydney, Australia (SPX) May 17, 2024

As the world grapples with the escalating climate crisis, one of the most pressing challenges is how to reduce atmospheric carbon dioxide (CO2) levels effectively. While reducing emissions is crucial, it is increasingly clear that reaching net-zero emissions alone will not suffice. To meet international climate targets and mitigate the worst impacts of global warming, we must also focus on developing and deploying scalable carbon removal technologies by 2050. Without such technologies, we could face significant challenges in stabilizing the climate and ensuring a sustainable future.

The Importance of Carbon Removal
The Paris Agreement, adopted in 2015, aims to limit global warming to well below 2C, preferably to 1.5C, above pre-industrial levels. Achieving these targets requires a two-pronged approach: drastically reducing emissions and actively removing CO2 from the atmosphere. This dual strategy is essential because, even with aggressive mitigation efforts, some sectors will continue to emit CO2. These sectors include agriculture, aviation, and heavy industry, where emissions are harder to eliminate completely.

Residual emissions from these sectors must be offset by carbon removal technologies to achieve net-zero emissions. Additionally, to bring atmospheric CO2 levels down to safer limits-potentially around 350 ppm, far below the current levels of over 410 ppm-we will need to remove excess CO2 actively. This effort is necessary to stabilize the climate and prevent long-term environmental damage.

The Threat of Overshoot Scenarios
In scenarios where global temperatures temporarily exceed the 1.5C or 2C thresholds, known as overshoot scenarios, the role of carbon removal becomes even more critical. Without scalable carbon removal, reversing temperature overshoot and bringing global temperatures back within safe limits would be extremely difficult. This is because natural processes alone, such as oceanic and terrestrial carbon absorption, are too slow to reduce atmospheric CO2 levels significantly in a short period.

Natural Carbon Sequestration Processes
Natural carbon sinks, including oceans, forests, and soils, play a vital role in absorbing CO2. However, these processes are inherently slow and limited in capacity:

1. Oceans: Oceans absorb about 25-30% of anthropogenic CO2 emissions. The CO2 dissolves in seawater and forms carbonic acid, which is eventually converted to bicarbonate and carbonate ions. However, this process slows down as the ocean becomes saturated with CO2.

2. Forests and Vegetation: Forests absorb CO2 through photosynthesis, making them crucial carbon sinks. Reforestation and afforestation can enhance this process, but the rate of absorption depends on the health and extent of these ecosystems.

3. Soils: Soils store carbon in organic matter. Practices such as no-till farming, cover cropping, and agroforestry can increase soil carbon storage, but the overall impact is still limited compared to the vast amounts of CO2 emitted annually.

Even under optimal conditions, these natural processes might reduce atmospheric CO2 by only 1-2 ppm per decade in the short term. Over centuries, they might achieve reductions of around 50-100 ppm. Given the current levels of over 410 ppm, this slow rate of reduction highlights the need for active intervention.

The State of Carbon Removal Technologies
Several technologies and methods are currently being developed to actively remove CO2 from the atmosphere. These include:

1. Direct Air Capture (DAC): DAC technologies extract CO2 directly from the air. The captured CO2 can be stored underground or utilized in products such as synthetic fuels. However, DAC is currently expensive and energy-intensive, requiring significant advancements to become viable at scale.

2. Bioenergy with Carbon Capture and Storage (BECCS): BECCS involves growing biomass, which absorbs CO2 during photosynthesis. The biomass is then converted into energy, and the CO2 produced is captured and stored. While promising, BECCS faces challenges related to land use, water resources, and potential impacts on food security.

3. Enhanced Weathering: This process involves spreading minerals that naturally react with CO2 on land or in the ocean, enhancing the natural weathering process that sequesters carbon. Enhanced weathering is still in the experimental stage and requires further research to assess its feasibility and environmental impact.

4. Reforestation and Afforestation: Planting new forests and restoring degraded ones can increase carbon sequestration. Although a natural process, large-scale implementation requires strategic planning and significant resources.

5. Soil Carbon Sequestration: Improving agricultural practices to enhance soil carbon storage offers potential, but widespread adoption and consistent results are necessary for significant impact.

Challenges and the Path Forward
The development and deployment of scalable carbon removal technologies face several challenges:

1. Technological Readiness: Many carbon removal technologies are still in the early stages of development. Scaling them up to the level required to make a significant impact will take time and investment.

2. Economic Viability: The current cost of carbon removal technologies is high. Reducing these costs through research, development, and economies of scale is essential for widespread adoption.

3. Infrastructure and Deployment: Building the infrastructure to capture, transport, and store or utilize CO2 at scale presents logistical challenges. Coordinated global efforts are needed to develop and manage this infrastructure.

4. Policy and Governance: Effective policies, incentives, and regulations are crucial to support the development and deployment of carbon removal technologies. International cooperation and governance frameworks are also necessary to ensure safe and effective implementation.

Beyond Tomorrow
By 2050, scalable carbon removal processes will be essential to meet climate targets and mitigate the worst impacts of climate change. While natural carbon sinks are crucial, their slow rate of CO2 absorption underscores the need for active intervention. Developing and deploying technologies such as Direct Air Capture, BECCS, enhanced weathering, and improved agricultural practices are vital steps toward achieving a stable and sustainable climate.

Without these efforts, the chances of meeting the Paris Agreement targets and stabilizing the climate are significantly diminished. It is imperative to accelerate the development, deployment, and scaling up of carbon removal technologies while continuing to reduce emissions through traditional mitigation efforts. This comprehensive approach is our best hope for ensuring a livable planet for future generations.

Infographic Report:Carbon Dioxide Removal

IPCC Report:Chapter 4 - Carbon Dioxide Removal