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Carbon removals will become a vital tool for reducing carbon concentrations in the atmosphere but only massive cuts in emissions will give humanity a fighting chance of keeping global heating to 1.5°C or below, says the UN’s Intergovernmental Panel on Climate Change (IPCC).

The latest IPCC report, which was released in April, outlines various pathways for mitigating the negative effects of the unfolding climate crisis. On the topic of carbon removals – which covers various approaches to suck greenhouse gases (GHG) from the atmosphere and store them on land, under the ground or in the ocean – the IPCC treads a cautious line. 

The scientists behind the report expect governments to focus on supporting research and development and targeted deployment rather than large-scale rollout. They point to the lack of understanding of the significant potential harm associated with carbon removal methods and the challenges of monitoring, verifying and accounting for removals. 

“The EU should take the IPCC’s reservations to heart and not rush into upscaling unproven removals with unknown but massive potential for harming people and planet,” urges CMW’s Wijnand Stoefs, who specialises in carbon removals, among other areas of expertise “However, we will need removals in the future, so now is the time to do our homework and build our understanding of these issues.” 

While it will be “unavoidable”, in the words of the report, to use carbon removals to “counterbalance hard-to-abate residual emissions”, i.e. essential emissions required for the healthy functioning of society, the IPCC emphasises, the primary focus must be on rapid, sustained and significant emissions reductions.

Not a model solution

“All global modelled pathways that limit warming to 1.5°C (>50%) with no or limited overshoot, and those that limit warming to 2°C (>67%) involve rapid and deep and, in most cases, immediate GHG emission reductions in all sectors,” the report says, highlighting the clarity of the science on the subject.

This is partly because carbon removals technologies are either in their infancy or largely untested at the kind of scale that would be required to make a difference to CO₂ concentrations already in the atmosphere, let alone to absorb even more continued emissions. 

Moreover, as the report points out, overreliance on carbon removals can derail or delay the truly urgent work of reducing emissions now. “This is being ignored by some European policymakers who would use removals to offset continued emissions through opaque and dysfunctional voluntary markets or even in mainstream EU climate policy, such as the EU carbon market or national emission reduction targets,” explains Stoefs. “Offsetting is not the way forward – removals have to come on top of emission reductions.”

In addition, many carbon removal techniques are expensive and, paradoxically, energy hungry. More worryingly still, relying on the wrong type of techniques, such as temporary biogenic removals to counterbalance fossil emissions, or on untested technologies could result in reversals or rising, instead of falling, emissions. 

The IPCC outlines three main uses for carbon removals technologies: to supplement significant emissions reductions, thereby accelerating climate mitigation; to balance out unavoidable residual greenhouse gas emissions to achieve net-zero emissions; or, even better, to achieve net-negative emissions by removing more carbon from the atmosphere than we emit.

Air of clarity

The IPCC’s concerns about the potential use and misuse of carbon removals chime with those of Carbon Market Watch – which is unsurprising, as both are based on the best available science. Although we can deceive ourselves, we cannot deceive the atmosphere. That is why we, at CMW, are convinced that emissions reductions are pretty much the only game in town for meeting the bulk of our climate targets.

“As with all efforts to slow down the climate breakdown, it is important to keep one thing in mind: the atmosphere cannot be cheated,” Stoefs points out. “While our immediate priority must remain to cut CO₂ pollution as fast as possible, carbon removals can, in the future, be used to take us over the finishing line and help us to reach climate neutrality or net-negative emissions. The EU should, therefore, keep removals out of its carbon market, and out of national emission reduction policies (the so-called Effort Sharing Regulation).”

Another vital factor highlighted in the IPCC report is the issue of accurate and honest reporting. Late last year, CMW released a report, titled ‘Respecting the laws of physics’, outlining the key principles required for effective carbon removals accounting. The EU has started a related legislative process (the so-called carbon removal certificatio mechanism), but seems intent on rushing removals without ensuring that accounting and reporting will be airtight.

One fundamental principle is that the targets and systems set up to count carbon removals must be separate from those measuring emissions reductions because net values obscure and obfuscate the picture of what is really going on – and falsely equate emissions and removals. This is demonstrably false because, for example, a tonne removed likely has a 10% lower impact on atmospheric CO2 concentrations than a tonne emitted due to interactions with land and ocean carbon stocks.

Another important principle is that removals counted towards climate targets must be real. This means that a removal process must deliver net-negative emissions along its entire life cycle – including energy, land and materials used. In addition, carbon must be taken out of the atmosphere, not from smokestacks, and it must be stored for at least several centuries and ideally much longer.