Why the Science Based Targets initiative should not allow carbon offsets

Statement signed by 29 scientists opposing carbon offsets.

The Science Based Targets initiative is currently reviewing its Corporate Net-Zero Standard. In April 2024, SBTi’s Board of Trustees announced that carbon offsets “could function as an additional tool to tackle climate change”.

This announcement came without any consultation with the staff working at SBTi or the SBTi Technical Council. REDD-Monitor summarised some of the responses to the announcement. My favourite came from Frederic Hache of the Green Finance Observatory:

In a shocking turn of events, a corporate and financial institutions’ climate action organisation decided to favour corporate and financial institutions’ economic interests.

In July 2024, SBTi published a synthesis of evidence submitted to SBTi on the effectiveness of carbon offsets. Joe Romm at the University of Pennsylvania described the synthesis report as “SBTi’s bombshell rebuke to offsets.”

Now 29 scientists have written a statement urging SBTi not to allow corporations to use carbon offsets to meet their climate targets. The statement comes shortly after the Bezos Earth Fund announced that it had stopped funding SBTi, a move the Financial Times describes as “the billionaire’s latest effort to curry favour with US President Donald Trump”.

Doreen Stabinsky, who is on the technical council of SBTi told The Guardian that,

“You look at Bezos and the folks he’s hanging out with in the billionaires club, and you realise this is about more than SBTi. Bezos is bowing down to Trump in a way a bunch of billionaires are bowing down to Trump.”

The statement is posted in full below — it was first posted on the media brand and sustainability in business website, edie:

The Science Based Targets initiative (SBTi) has become a leading force in corporate climate governance, helping businesses align their emissions reductions with the Paris Agreement. Yet, of late, the SBTi’s commitment to science-based approaches has come under question, as it debates the possibility of allowing companies to use carbon offsets to meet their climate targets, as part of an ongoing review of its Corporate Net-Zero Standard. As decades of research have demonstrated the flaws of carbon offsets, embracing them would be a clear departure from the commitment to science-based approaches by the SBTi.

The SBTi’s flirtation with offsets comes at a critical juncture in global climate action. Several large corporations have backtracked on their climate and sustainability commitments of late, and at COP29 in Azerbaijan, rules for carbon credits under Article 6 of the Paris Agreement were agreed upon that have drawn criticism for prioritizing the interests of wealthy countries, allowing them to pay for emission reductions elsewhere instead of cutting their own.

This trend of sidelining the integrity of climate targets over short-term interests by State and non-state actors alike makes the SBTi’s role as a science-based standard setter more critical than ever.

The SBTi’s current framework rightly prohibits the use of carbon offsets to meet near- and long-term targets. This forces companies to focus on reducing emissions in ways that are measurable, permanent, and verifiable. But now this strong stance could be weakened, especially with regard to Scope 3 emissions – the indirect greenhouse gas emissions generated throughout a company’s value chain. Allowing offsets for Scope 3 emissions would undermine the SBTi’s credibility and delay the necessary transition to a fossil-free society.

Common credibility issues with offsets

Carbon offsets are achieved either through avoided emissions or enhanced removals. Avoided emissions enable companies to fund projects that claim to reduce or prevent emissions elsewhere — like forest protection or renewable energy initiatives — rather than cutting their own emissions. While these projects theoretically “balance out” a company’s emissions, they often rely on speculative baselines (such as pre-project deforestation rates, or rates of expansion of solar power). This makes it impossible to verify whether reductions are truly “additional”, meaning they wouldn’t have occurred without the project that generated carbon credits. This problem is common with avoidance-based offsets, where projects are designed to prevent emissions that might never have happened in the first place.

Enhanced removals aim to sequester carbon in bedrock, or in biogenic carbon sinks, often through nature-based solutions (NBS) like reforestation or soil carbon projects. However, these solutions are inherently uncertain. Plants, which absorb carbon through photosynthesis, belong to the so-called fast carbon cycle, where carbon moves between the atmosphere, oceans, plants, and soils — in a natural flux that balances emissions and uptake. Fossil carbon, by contrast, is locked in the slow carbon cycle, stored in bedrock for millions of years. Burning fossil fuels at current rates releases this carbon 94 times faster than volcanic activity, the main natural process that transfers fossil carbon into the fast cycle. This contributes to lasting climate impacts that short-term sequestration from NBS cannot mitigate.

Additionally, forests can burn or be logged, and soil carbon is easily released by changing agricultural practices. While biogenic sinks are vital and should be enhanced in ecologically sound ways, they are temporary and lack the permanence required to offset continued fossil emissions. Worryingly, a warming climate may weaken or even reverse the capacity of ecosystems to absorb carbon, making reliance on NBS both an unrealistic and irresponsible climate strategy.

The issue of land availability further complicates reliance on offsets. Productive land is a limited resource needed to support a growing demand for food, energy and fibre. There is simply not enough productive land globally to meet the demand for carbon offsets. Furthermore, large-scale tree-planting projects risk displacing vulnerable pastoralists and small-scale farmers. The idea that forest carbon projects may deliver a “triple win”, in the form of simultaneously enhancing rural livelihoods, biodiversity, and carbon storage, fails to address critical inherent conflicts between these objectives. Decades of research have shown that carbon projects, despite social and environmental standards and third-party verifications, fail to deliver credible carbon credits and tend towards producing social harm.

Risk of delayed decarbonisation

Offsets are often heralded as a cost-effective climate solution, but in practice, they provide a loophole that lets companies delay the systemic changes required for deep decarbonization. Instead of investing in clean technologies and phasing out fossil fuels as quickly as possible, companies can purchase cheap offsets to “neutralize” emissions on paper. Reliance on market mechanisms delays meaningful decarbonization and incentivizes greenwashing over genuine climate action. Worse, this approach undermines companies that genuinely seek to cut emissions ambitiously under the SBTi guidance, by allowing competitors the unfair and shortsighted advantage of relying on offset-based strategies.

To safeguard its integrity, the SBTi must uphold its prohibition of the use of offsets towards meeting targets. It can still encourage companies to support global climate and sustainability initiatives through Beyond Value Chain Mitigation. Under this framework, companies can fund projects outside of their value chains—such as carbon dioxide removal technologies like biochar or Bioenergy with Carbon Capture and Storage (BECCS)—without counting these efforts towards their own climate targets. Such carbon dioxide removal projects do have a role to play in mitigation strategies, but cannot replace the responsibility to reduce operational emissions. There are also constraints placed on its upscaling, both by limited CO₂ storage capacity and by the sustainability of using large tracts of productive land for biomass production.

As the SBTi revises its Net-Zero Standard, it must strengthen its commitment to driving real emissions reductions within companies’ operations and value chains. Offsets, with their inherent flaws, must remain excluded from claims of progress towards climate targets. By maintaining its rigorous science-based standards, the SBTi can continue to lead in corporate climate responsibility, ensuring that climate targets deliver measurable, tangible action instead of empty net-zero promises.

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Signatories:

Niclas Ericsson, Swedish University of Agricultural Sciences. Researcher in Sustainable production and consumption
Flora Hajdu, Swedish University of Agricultural Sciences, Professor of Rural Development
Mats Björk, Stockholm University, Professor of Marine Plant Physiology
Alasdair Skelton, Stockholm University, Professor of Geochemistry and Petrology
Glenn Bark, Luleå University of Technology, Senior Lecturer in Geology
Maria Johansson, Researchers Desk, PhD in Ecology
Jeannette Eggers, Swedish University of Agricultural Sciences, Researcher in Forest Management Planning
Paul Glantz, Stockholm University, Associate Professor in Atmospheric Science
Jens Friis Lund, University of Copenhagen, Professor of political ecology
Nils Markusson, Lancaster University, Senior Lecturer in the Politics of Environmental Technology
Joanna D. Haigh, CBE FRS, Imperial College London, Emeritus Professor of Atmospheric Physics
Richard Pancost, University of Bristol, Professor of Biogeochemistry
James Dyke, University of Exeter, Associate Professor in Earth System Science
Alice Larkin, University of Manchester Energy Beacon Lead, Tyndall Centre for Climate Change Research, Professor of Climate Science & Energy Policy
Daniela Guasconi, Stockholm University, Postdoctoral researcher in Physical Geography
Tor A. Benjaminsen, Norwegian University of Life Sciences, Professor of Environment and Development studies
Andrew Ringsmuth, University of Graz, Lecturer in Complex systems science and Social ecology
Hanne Svarstad, Oslo Metropolitan University, Professor in Development Studies
Peter Newell, University of Sussex, Professor of International Relations
Dr Kate Dooley, University of Melbourne, Senior Research Fellow in Carbon accounting and Forest governance
Wim Carton, Lund University, Associate Professor of Sustainability Science
Caroline Greiser, Stockholm University, Researcher in Physical Geography
Kristoffer Hylander, Stockholm University, professor in Ecology
Stig-Olof Holm, Umeå University, Lecturer in ecology and environmental sciences
Linda Engström, Swedish University of Agricultural Sciences, Researcher in Rural Development
Lowe Börjeson, Stockholm University, Professor in Geography
Duncan McLaren, American University, Washington DC, Visiting Fellow – Forum for Climate Engineering Assessment
Will Lock, University of Sussex, Lecturer in International Development
Kirstine Lund Christiansen, University of Copenhagen, PhD fellow of political ecology