What the latest IPCC report says about carbon removal
by Anu Khan, deputy director of science and innovation
Eight years ago, the IPCC first mentioned carbon removal as a necessary step for addressing the climate crisis. Soon after those words appeared in the Fifth Assessment Report, Carbon180 was founded to ensure that this little-known solution with an outsized impact on our climate goals would be able to scale in time.
This week, the IPCC released the third part of its Sixth Assessment Report, marking another major milestone in the global conversation around carbon removal. Though the report covers a broad range of mitigation solutions, it has been called the carbon removal report, providing a definitive answer to the question, “Do we really need CDR?”
Here, we’re going to dig into exactly what the report says about the role of carbon removal in achieving climate goals, key considerations for scaling, and how carbon removal intersects with other mitigation pathways.
Carbon removal is essential
The report is a massive accounting exercise that attempts to determine how much carbon we can emit before hitting certain levels of warming and how likely we are to use up that “carbon budget.” The IPCC says that existing and planned fossil fuel infrastructure uses up most of our budget for 2°C of warming. Climate models suggest that the most likely scenario is we overshoot and then return to 1.5°C warming, but without stronger policies, we could be on track for 3.2°C by 2100.
Emissions reductions are essential to stop warming, and carbon removal is necessary to address impacts of climate change we’re already feeling today. Though attempts have been made in the past to estimate the total amount of negative emissions needed under various scenarios, the IPCC has finally put a number on it: We’ll need global cumulative net-negative emissions of 380 GtCO2 from 2050 to 2100 to return to 1.5°C after a likely overshoot. Rapid emissions reductions are still critical — with swift action, we can reduce the need for carbon removal, but never eliminate it.
The models suggest how this might play out. Negative emissions will first come from land-based activities such as reforestation. Later in the century, carbon removal technologies like BECCS and DAC, that pull CO2 from the air and store it safely in products or underground, will play a larger role.
Key factors for scaling carbon removal
So, we have a number — 380 GtCO2 removed by 2100. But what will it look like to responsibly scale CDR to meet this goal?
CDR is not one-size-fits-all
Carbon removal solutions will be deployed in different places across the country and globe and at different times over the next century based on their technological readiness, storage and transport needs, co-benefits and risks, cost, and — most importantly — potential to scale.
Given this diversity of approaches, deployment of CDR solutions requires careful consideration of impacts on communities and ecosystems, including both risks and benefits.
The time is now
The report describes three roles for CDR over the next few years. Near term, CDR can complement emissions reductions efforts that are limited by currently available technology; next it can help zero out residual emissions from hard-to-abate sectors; at the end of the century, carbon removal will help us achieve net-negative emissions and bring temperatures back down from their peak.
Four key enablers
Carbon removal pathways require policy support along the entire innovation pipeline:
- funding to speed up fundamental research,
- support for demonstration projects,
- incentives to drive supply and demand for carbon removal services, and
- better tools for measurement, reporting and verification of carbon. (More on this from C180 soon.)
Carbon removal across sectors
Carbon removal won’t be addressing climate change alone. The report also explored the myriad sectors that will, at some point in the future, intersect with CDR.
Alongside a major transition away from fossil fuels, the report says that carbon removal is essential for reaching net-zero emissions from the energy sector.
Agricultural and forestry practices can produce both emissions reductions and remove carbon in the short term, but these mitigation measures cannot fully balance out the slower pace of decarbonization in other sectors. Technological carbon removal solutions like DAC can complement reductions and removals from the land sector.
Carbon removal will be needed to address residual emissions from especially hard-to-abate sectors. Point-source capture will also likely play a role in decarbonizing the industrial sector. Scale-up of both these solutions requires expanded access to dedicated geologic storage. Innovation, policy support, and public engagement are needed to accelerate the development of storage solutions.
The chemicals sector can also reduce emissions by replacing fossil fuel feedstocks with other sources of CO2. This tech is still at an early stage, and does not yet figure into the IPCC’s models, but it could represent a significant change in our carbon economy.
CDR advocates can and should not only work with other sectors but learn from them. This is the first IPCC report that digs into the importance of innovation policy for climate mitigation solutions like renewables and energy storage. The authors find that a mix of innovation-focused policies played an important role in driving down the costs and driving up deployment of wind, solar, and batteries. Even more importantly, the report highlights the need for well-designed innovation policy to realize the social and environmental co-benefits of new technologies.
What does this mean for carbon removal today?
It means we’re on the right track, and we have a lot of work left to do. Ambitious, rapid growth of the CDR sector to a climate-relevant scale is possible and necessary. What worked for batteries, solar, and wind can work for CDR. Policy will be the most impactful lever for filling in research gaps, driving down costs, and ensuring an equitable and just scale-up.
As discussed above, the IPCC identified key areas where policy can support carbon removal. Today, we’re focusing our work here as well, specifically advocating for:
- Policy support for innovators and entrepreneurs to demonstrate novel solutions that are not yet economically viable, and therefore do not show up in the IPCC’s models, but could be transformative. This includes pathways like direct ocean capture and carbon utilization for chemicals.
- Additional research on and tools for measurement, reporting, and verification of carbon stocks.
- Pull incentives, like government procurement, to stabilize demand in the nascent carbon removal market and catalyze gigatons of removal.
Activating these levers for carbon removal will only pay off if done in a way that ensures projects integrate community priorities and offer economic and environmental co-benefits. With this report, our mission, and our vision as our guides, we’ll continue championing CDR to build a carbon-removing future in which all can thrive.
Edited by Emily Reich