Carbon offset prices can cut or raise emissions, new equilibrium model finds

A new academic paper says higher carbon offset prices do not mechanically translate into lower emissions once the broader economy is taken into account. In the model, raising the price of offsets can either cut or raise economy-wide emissions, depending on how markets respond.

The paper, "General Equilibrium Effects of Carbon Offsets," was posted on arXiv on June 24, 2026, with the abstract page dated June 25, 2026. It is written by Isla Globus-Harris and Daniel H. Karney.

The authors study carbon offsets in a general-equilibrium framework, which means they look beyond the offset project itself. Their model tracks how offset payments can ripple through prices, production decisions, emissions and welfare across the wider economy.

What the model says

The central result is ambiguity. In the paper’s framework, a higher offset price can reduce total emissions in some cases, but increase them in others. The welfare effect is also ambiguous.

That matters because offset policy is often discussed as if paying more for credits should automatically produce more climate benefit. The paper argues that spillover effects can break that simple relationship.

The authors also say offsets are often over-credited under many parameterizations of the model, meaning the credited emissions benefit can exceed the actual effect. But the model does not point only in that direction: under-crediting can also occur in some cases.

How the paper frames the problem

The study identifies four margins through which offsets can respond to payments, including one margin the authors say had not previously been identified. That is one reason the paper argues conventional offset accounting can miss important economy-wide effects.

The paper also says neither of the carbon-accounting metrics used in the study is a sufficient statistic for welfare. In plain English, that means the metrics do not fully capture the broader social consequences of the policy.

The authors’ policy point is not that offsets are useless, but that their climate effect depends on general-equilibrium spillovers. If those spillovers are large, the emissions gains buyers expect from offset purchases may be weaker, reversed or more complicated than project-level accounting suggests.

Why the timing matters

The paper appears first as an arXiv release, making this a fresh research peg rather than a policy announcement or an empirical verdict on a specific offset program. The submission timestamp on the abstract page is listed as June 24, 2026, and the abstract page shows June 25, 2026.

That chronology matters for readers because the work is new enough that outside commentary may still be developing. For now, the strongest verified claims come from the paper itself, not from a journal publication, conference presentation or formal policy response.

The research is also theoretical rather than a field test of a real registry or project. Its findings should be read as a model-based warning about how offset markets can behave in principle, not as a direct measurement of one real-world carbon market.

Why policymakers care

Carbon offsets are often sold as a straightforward way to pay for emissions cuts or removals elsewhere. This paper argues that once economy-wide spillovers are included, the accounting becomes less straightforward.

That makes the work relevant to carbon-market design and carbon-accounting rules. If offset prices influence production, output and other market decisions beyond the credited project, the resulting emissions and welfare effects may diverge from what conventional accounting would predict.

The paper’s broader warning is that market spillover effects should be considered when evaluating offset policy. Buyers, regulators and standards-setters may need to think about more than project-level crediting if they want to understand the full climate impact.

What to watch next

The next useful question is whether a university, lab or working-paper page republishes the study with author affiliations or additional context. Independent economics or climate-policy coverage would also help clarify which assumptions drive the strongest results.

Follow-up commentary from the authors, seminar slides or a conference presentation could sharpen the policy implications further. For now, the paper’s main takeaway is that offset pricing can have ambiguous economy-wide effects, and carbon accounting may miss some of the channels that matter most.