IPCC WGIII Report Affirms the Necessity for CDR to Meet Goals of the Paris Agreement

Two opposing mega-trends are highlighted by the IPCC Working Group III report, one a cause for grave alarm, one a cause for hope. This report finds we are currently heading very fast towards global warming of 1.5°C. And the current pledges by countries would take us significantly well beyond the 1.5°C target. 

A major takeaways from this report indicate that we must dramatically phase down fossil fuels and stop new fossil-fuel infrastructure.  However, at the same time as we phase down fossil fuels, the IPCC report finds that carbon dioxide removal (CDR) is required to counterbalance hard-to-abate sectors of the economy and to limit warming to 1.5°C. The IPCC report affirms that carbon removal is especially important to counterbalance hard-to-abate sectors, like steel production and long-haul aviation. 

For a more extensive look into the finding of this report, please see our “Key Findings for Carbon Dioxide Removal.”

Here is a summary of some key points:

The IPCC Working Group III report affirms that carbon removal will be critical to meet the goals of the Paris Agreement, in tandem with deep cuts to emissions, and highlights the scaling that needs to happen to realize this goal. 

  • CDR can counterbalance hard-to-abate sectors: The report finds that CDR has an important role to play in reaching net-zero emissions by counterbalancing residual emissions in sectors of the economy like food production, long-haul aviation, and steel production (C.11.4). CDR is required both globally and nationally (Technical Summary, page 94).
  • Carbon removal cannot be an excuse to overshoot 1.5: The Working Group II report found that scenarios that significantly overshoot 1.5°C, including ones where large-scale CDR is used, bring catastrophic costs and other risks. The Working Group III report acknowledges the current limitations of CDR as well as the risks and impacts (C.11.2; C.11.5), stating that upscaling the deployment of CDR at very large scales depends on developing approaches to address feasibility and sustainability (C.11).
  • Responsible deployment is key: The report warns that poorly done CDR can have varying socio-economic side effects, depending on the method, site-specific content, implementation, and scale of CDR deployment (C.11.2). As a result, it is crucial to responsibly scale-up CDR. 
  • Multiple CDR solutions can work in tandem with one another: The report does not make a recommendation on which CDR approach is best. The estimates of carbon removal available from each CDR approach vary in the report. In addition, all approaches have limits and trade-offs. The report finds that CDR in the land sector alone presents challenges for competing demands on food security, conflicts with livelihoods, and the nuances of land ownership and management systems (C.9). The report finds that regarding mitigation generally, a broad portfolio is best and that portfolios of technological solutions reduce feasibility risks (Technical Summary, page 138) In this light, investing in multiple CDR approaches may be required to reach the gigaton scale of removal needed. This portfolio of options includes technological approaches like Direct Air Capture, which requires significantly less land area than nature-based solutions.   
  • Carbon removal is distinct from carbon capture: The IPCC places CDR and Carbon Capture and Storage (CCS) in two distinct sections of the report. The terms often get conflated. CDR and CCS are two diverse approaches to climate mitigation that use similar and overlapping vocabulary but undertake very different activities, often with radically different approaches. Carbon removal can address legacy emissions, which makes it a unique tool for meeting the goals of the Paris Agreement. Conversely, CCS stops carbon dioxide before it gets into the atmosphere. 
  • Scaling up CDR is crucial: The report finds that scaling up CDR responsibly requires accelerated research and development, improved tools for risk assessment and management, targeted incentives, the development of agreed methods for measurement, and robust reporting and verification of carbon flows (C.11.5). Modeling in the report does not fully account for the falling costs of CDR, but general economic cost forecasts by prior IPCC reports failed to fully capture cost reductions that subsequently occurred for solar and wind power (Technical Summary, page 25). The report finds that modular small-scale technologies tend to improve faster and be adopted more quickly – a technological profile that may match DAC units (Technical Summary, page 25). 

It is critical to responsibly scale up carbon removal to removal in order to balance the carbon budget and limit warming at 1.5°C.

  • The world is close to exceeding its carbon budget: A significant but very small carbon budget remains to limit warming to 1.5° and the path to limit warming to 1.5° is extremely narrow. Pollution from hard-to-decarbonize sectors must be counterbalanced.
  • Carbon removal is needed to help close the gap: Carbon removal, which can counterbalance emissions in hard-to-abate sectors, with nature-based and technological solutions, can help ensure the world does not exceed its carbon budget if (and only if) it is paired with aggressive pollution reduction.  
  • We need to embrace all climate solutions: As the world gets close to exceeding our carbon budget, there is no silver bullet to solve the climate crisis. We need to double down on urgently reducing new climate pollution. This can happen in tandem with carbon removal and other climate technologies. Investing in carbon removal today can help answer questions on responsible carbon removal deployment, such as how to reduce costs and ensure that projects are developed with community input.


ICRLP Webinar Explainer Series Provides A Deeper Understanding on Many Issues Surrounding Carbon Dioxide Removal

One of the streams of work for The Institute for Carbon Removal Law and Policy is to provide broad education on carbon removal approaches and implications. Carbon removal is a big and complex subject matter, with much to unpack and debate. With this in mind, we launched our “Assessing Carbon Removal Webinar Explainer Series” in 2018. 

These one-hour webinars bring together Institute staff and guest speakers to explain what is known about varying carbon removal approaches and to explore big themes. The presentations and conversations delve into research needed to assess technical, legal, and social aspects and considerations of carbon removal technologies.,

Most recently presented in this series have been webinars on Agroforestry and Carbon Removal and Corporate Commitments, both of which have accompanying blog entries that outline the main points covered in the presentations, which can be found on ICRLP Carbon Removal Blog Posts page.

In addition to these recent webinars, there are a number of past presentations that provide a wealth of knowledge on carbon removal:

  • Enhanced Oil Recovery: A discussion on the technological, economic, and political issues associated with Enhanced Oil Recovery (EOR), including the costs involved, the project development perspective, EOR relative to saline storage necessary to scale up carbon storage, and why EOR should be decoupled from the decarbonatization agenda and policy.
  • Mitigation Deterrence: Mitigation Deterrence (MD) is where the pursuit of greenhouse gas removal (GGR) delays or deters other mitigation options. This webinar presents the results of a project that analyzes this issue and explores conditions in which GGR technologies can be used with minimal MD.
  • Direct Air Capture: The presentations within this webinar provide a comprehensive overview of mechanisms behind Direct Air Capture of carbon dioxide, which is the practice of utilizing chemicals to remove carbon dioxide from the air. 
  • Enhanced Mineral Weathering: This webinar presents the ins and outs behind varying proposed methods of Enhanced Mineral Weathering utilizing an array of minerals on land and in the oceans. 
  • Governance of Marine Geoengineering: This webinar followed the release of a CIGI Special Report on this topic. The presentations dig into the potential role of marine climate geoengineering approaches such as ocean alkalization and “blue carbon,” with a focus on the governance, research, deployment and potential risks associated with these approaches to carbon dioxide removal.
  • Communicating Carbon Removal: This webinar was presented following the release of ICRLP report “The Carbon Removal Debate” and explores the challenges associated with communicating the necessity for, and options behind, carbon dioxide removal.
  • The Brazilian Amazon Fires: What Do They Mean for the Climate?: As thousands of fires ripped across the Amazon in 2019, wreaking havoc and devastation, this webinar seeks to explore what these fires mean for the climate, and lessons are to be learned regarding global forest protection.
  • Soil-Based Carbon Removal: Soil harbors three times more carbon than is present in the atmosphere, and this webinar investigates whether healthy soils can help tackle climate change. Experts on the panel provide a scientific overview of soil carbon sequestration while examining the risks, benefits, and uncertainties.  
  • NAS “Negative Emissions Technologies and Reliable Sequestration: A Research Agenda” Report: This report released by the National Academy of Sciences, Engineering, and Medicine is the focus of discussion in this webinar. A few of the points addressed are the current state and potential for negative emissions technologies, conceptualizing scale in addressing climate change, and the impact of carbon removal on land use and soil, among others.
  • Potential Role of Carbon Removal in the IPCC’s 1.5 Degree Special Report: The panelists in this webinar examine this special report, released by the IPCC in 2018, examine what this report says about many aspects of carbon removal such as the potential need, governance, and classification. 
  • What We Know and Don’t Know about Negative Emissions: This webinar is aimed at providing a systematic overview of negative emissions technologies, discussing the status of research, ethical considerations, and how to spur future innovation and upscale research for advancing utilizations.
  • Accessing Carbon Dioxide Removal: As the introductory webinar that kicked off the series in 2018, the panelists dive into what carbon removal technologies are, their role in the portfolio of response to climate change, risks, ways to manage technologies in beneficial ways, and what the future could potentially hold. This webinar in particular serves as a valuable springboard for those who are relatively unfamiliar with carbon removal and seeking to learn more. 

All of these webinars are also available to view on our YouTube channel and on the ICRLP website. As this series continues to evolve, we encourage you to stay tuned for upcoming webinars going forward. If you are interested in joining our mailing list to receive notifications of upcoming webinars and our Newsletter, feel free to reach out to us at icrlp@american.edu.

Reflections on the IPCC special report on pathways to and impacts of 1.5ºC

Author: Matthias Honegger

This post originally appeared on the blog for the Institute for Advanced Sustainability Studies (IASS).

How is this report different from previous IPCC reports?

The main difference to previous reports issued by the Intergovernmental Panel on Climate Change (IPCC) is that, according to the last assessment report, we have now used up the so-called “carbon budget” for the 1.5°C target. Therefore, in principle, we should not emit another single ton of CO2 going forward. The last report did not pay much attention to the 1.5°C target because too few studies even addressed this ambitious scenario. The Paris Agreement and the request to the IPCC for this latest report have changed this: more and more studies have considered how the goal could be achieved – with similar results, but greater urgency. What has changed since the last assessment report is that we are running out of time. More and more observers rate it as extremely unlikely that we can still get close to 1.5°C without the use of controversial solar geoengineering to directly alter the energy balance of the planet (also known as “Solar Radiation Management”). The latter is mentioned in the report as Solar Radiation Modification, but dismissed as too risky and insufficiently understood, which is understandable given the necessarily cautious approach of the IPCC in light of the still limited amount of research dedicated to seriously exploring the possibilities of SRM. However, a growing number of climate modelling studies consistently conclude that the use of SRM to partially counteract warming could help contain climate change and possibly avoid much suffering and harm. The same studies also consistently find that SRM could under no circumstances be a substitute for CO2 reduction and CO2 capture, but would potentially be useful as a risk-reducing supplement.

What political signals does the report send?

In the context of international climate policy the special report is expected to serve as a wake-up call for decision-makers. The IPCC report shows that the 1.5°C target, which in Paris gave hope to the most vulnerable populations, is slipping through our fingers. Unless the international community immediately and dramatically changes course, this goal is no longer within reach. A study from last year, which to my knowledge is not quoted in the report, found a one percent (1%) likelihood that warming would remain at 1.5°C if current trends continue. The international community is not even on a path to the less ambitious 2°C target. If today’s nationally determined contributions (NDCs) are implemented unchanged, warming is expected to reach 3°C above pre-industrial levels by 2100 – and more beyond the turn of the century. With millions of people depending on robust climate policy to secure their futures, this state of affairs should not be taken as an excuse to give up. The report unequivocally states that warming of 1.5°C would cause much less suffering and harm than warming of 2°C. There is not a shred of doubt that the corresponding steps must be taken now.

To what extent does it still make sense to talk about the 1.5ºC or 2ºC target? Do we have to admit that these goals are now barely achievable?

Achieving the 1.5°C goal with existing means of CO2 emission reductions will require drastic measures comparable perhaps only to the transformative efforts undertaken by societies in the face of war. The vast majority of scenarios assume that billions of tons of CO2 will also have to be removed from the atmosphere through the widespread application of emerging technologies such as bioenergy and CO2 capture and storage (BECCS) or the direct air capture and storage of CO2 (DACS) – with the corresponding costs. However, both of these approaches present their own challenges when deployed on this scale and have accordingly been largely ignored by decisionmakers to date. The use of bioenergy could potentially result in massive land use conflicts, while direct air capture requires vast amounts of energy and is, in its present state, both under-researched and prohibitively costly. Politics should not rely on such approaches without doing what is necessary to shape them into feasible policy options, and yet that is what happens every time we calculate our chances for the 1.5°C or 2°C target.

What are we to make of the current situation?

The IPCC authors were faced with the dilemma that the 1.5°C target is now practically out of reach despite significant political efforts to reduce or remove CO2 emissions. In conversations with colleagues in climate research, it has repeatedly struck me that many consider it unethical to even consider the possibility that current forms of action could fail to achieve the goal: Many colleagues suspect that expressions of doubt would undermine the political will to further pursue these crucial measures. Whether this is indeed the case is hard to answer and pragmatic optimism definitely has an important role to play. However, I think society has a right to be fully informed by science: We should all be aware of the risk-laden future we are approaching and not limit our focus to the best possible scenario. Accordingly, we would not be well advised to prematurely exclude potential options – from emissions reductions to adaptation, CO2 removal and solar geoengineering (SRM) – even if these options do not appear perfect at first glance and require further research. Anyone who deals with financial investments knows about the necessity of diversification when dealing with risks.

The full report can be found here on the IPCC website.


Matthias Honegger is a project scientist at the Institute for Advanced Sustainability Studies (IASS) in Potsdam, Germany. In his role there, he focuses on the question, whether biased risk perceptions of climate engineering contribute to a marginalization of climate engineering as a potential element of a broader strategy to address climate change. He is also exploring the current climate policy regime to identify governance elements, which could help consider carbon removal technologies and eventually solar radiation management approaches in an adequate manner within the international climate regime.