Carbon dioxide removal: How crucial is the next decade for this novel technology
Carbon dioxide removal, or CDR, is widely recognised as essential for attaining climate goals. CDR involves capturing carbon dioxide from the atmosphere and storing it for decades to millennia in land, ocean, geological formations, or manufactured products such as biochar.
The Intergovernmental Panel on Climate Change (IPCC), in its latest report, included 541 pathways that can limit global temperature rise to 1.5 degrees Celcius or 2°C. Almost all of these pathways involve some degree of CDR.
Scaling of CDR, also referred to as ‘negative emissions,’ is an effective way to attain the temperature goals set by the Paris Agreement, said Artur Runge Metzger, former director of the European Commission’s Directorate-General for Climate Action.
The University of Oxford has recently launched a significant report — The State of Carbon Dioxide Removal. A press release by the university called it a first-of-its-kind, independent scientific assessment tracking the development of CDR globally.
There are two ways to remove carbon dioxide: The conventional method involving land management, primarily via afforestation and reforestation and ‘novel CDR methods’, as the report refers to them.
Novel CDR methods involve storing captured carbon in the lithosphere, ocean, or products.
Currently, over two billion tonnes of CO2 (GtCO2) per year are being removed globally, according to the report. This is less than the current annual CO2 emissions by fossil fuel and cement sectors (36.6 GtCO2), but it may be more than many would anticipate.
The current CDR of two GtCO2 per year (99.9 per cent) comes from conventional sources. And only 0.002 GtCO2 (0.1 per cent) is from novel CDR methods such as bioenergy with carbon capture and storage, biochar and direct air capture with carbon capture and storage, the document stated.
Though novel methods receive more coverage, they are primarily at the pilot stages of development. The certainty about their costs, benefits, and hazards is minimal, but they can offer more durability carbon storage than trees and soils.
The next decade is crucial for novel CDR since the amount of CDR deployment required in the second half of the century will only be feasible if we see substantial new deployment in the next ten years or the CDR’s formative phase.
The report traced substantial growth in CDR’s innovation, research and public consciousness.
Despite scientific literature on climate change accounting for fewer than four per cent, studies on CDR are expanding exponentially at a rate of roughly 19 per cent per year (1990-2021). Currently, annual publications double every three to four years.
Innovation in CDR is growing significantly. Governments are investing in public research and development.
Though concentrated geographically, public funding for CDR totalled around $4.1 billion between 2010 and 2022.
Proposed direct air capture demonstration hubs in the United States account for the most traceable public funding ($3.5 billion). Investment in new CDR capacity totalled approximately $200 million between 2020 and 2022.
The report analysed the presence of CDR on social media platforms. Approximately 470,000 tweets in English, related to CDR, have been posted on Twitter since the platform’s launch in 2006.
The number of tweets on CDR has an average growth rate of about 33 per cent every year. This is quicker than the average increase in the overall number of tweets recorded on the platform (17 per cent increase) and the growth in tweets about climate change (10,000 per day in 2021, with a 28 per cent yearly growth).
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The report pointed out the gap between the CDR planned by countries and the amount of CO2 removal required to fulfil the Paris temperature goal.
In 2030, global scenarios that limit warming to 2°C or lower indicate additional CDR of 0.96 (0 to 3.4) GtCO₂ per year, compared to 2020. In contrast, countries have pledged an additional 0.1-0.65 GtCO2 by 2030 in their Nationally Determined Contributions (NDCs), a range that corresponds to unconditional and conditional NDCs. This suggests there is already an emerging CDR gap by 2030.
Only a handful of countries (53) have employed long-term mitigation strategies and a few (22) among them have CDR in their budget estimates.
For such countries, the CDR by 2050 amounts to 1.5 to 2.3 GtCO2 per year. Yet, the report found a significant gap relative to the average CDR (given by IPCC) required in pathways that limit warming to 1.5C or 2C of 4.8 GtCO2 per year by 2050.
Where there are examples of focused governance for carbon dioxide removal, they are mostly at the level of individual nations and the European Union. The United Nations Framework Convention on Climate Change and other multilateral organisations’ recommendations and initiatives are limited.