What we are missing about the update to the Absolute Contraction Approach

The ACA update and the OER framework

Historically, SBTi has been interpreted — rightly or wrongly — as a reduction-only framework. Reduce emissions in line with a pathway, and deal with the residual at the end.

There is now a second mechanism doing real work: the Ongoing Emissions Responsibility (OER) framework. This is introduced in CNZS v2, quite deliberately, as a second track that operates alongside the reduction pathway:

• the ACA governs how fast emissions come down
• OER governs how companies account for the emissions that remain while that is happening

That’s a structural change. Not a tweak.

What the ACA update actually does in that context

The ACA adjustment looks, in practical terms, like a recalibration of the near-term trajectory. Less front-loaded, more spread over time. Whether you see that as pragmatic or problematic is a separate question.

But mechanically, it has one unavoidable effect:

it increases the volume of emissions that exist on the pathway, rather than being removed by it, in the near to medium term.

Those emissions are not outside the system. They are inside it.

Which raises a more interesting question than “is ambition weaker?”:

where do those emissions now sit, and how are they being treated?

OER is where they sit

OER is often described as a voluntary add-on. That’s not how it functions in the draft.

It is the only part of the Standard that directly engages with the fact that companies will continue to emit while they transition.

And crucially, it does that without relying on compensation logic.

That’s the real innovation.

Because it creates a category of action that is:

• not abatement
• not neutralisation
• not offsetting

But still recognised as part of credible net zero action.

That space simply didn’t exist before in a formalised way.

So the interaction is not subtle

If you ease the pressure on the abatement curve in the near term — even slightly — you are not reducing the problem.

You are reallocating it.

You are moving a portion of what would have been addressed through immediate reductions into a category of emissions that persist along the pathway.

And those emissions have to be dealt with somewhere.

In CNZS v2, there is only one place for them to go.

This is why OER becomes more central, not less

This isn’t about “increasing demand” in a narrow, market sense. It’s more fundamental than that.

The ACA defines the pace of transition.

OER defines the credibility of that transition while it is happening.

If the pace slows at any point along the curve, the burden on credibility increases.

And OER is the only mechanism in the Standard that can absorb that burden without reverting to offsetting claims.

There’s also a political economy here

SBTi is trying to hold two things together:

• maintain scientific credibility
• keep companies engaged

The ACA update speaks to the second.

OER is what allows that adjustment to be made without collapsing the first.

Because it creates a channel through which companies can continue to be seen to act on their emissions, even where those emissions are not being reduced as quickly as originally envisaged.

That’s not an accident. It’s design.

What most commentary is missing

The current debate is treating ambition as if it sits entirely in the reduction pathway.

That was a reasonable assumption under the old model.

It isn’t anymore.

Ambition is now split across:

• how quickly emissions are reduced
• and how seriously companies take responsibility for the emissions that remain

You can criticise one without looking at the other, but you’re only seeing half the system.

Where this leaves things

If the ACA adjustment results in a slightly more gradual near-term trajectory, then yes — more emissions persist for longer.

That’s not the end of the story. It’s the starting point.

Because the integrity of the system now depends on whether those emissions are:

• ignored
• compensated
• or taken responsibility for in a way that is credible

OER is the mechanism that determines which of those three outcomes dominates.

Bottom line

The ACA update doesn’t tell you whether the system is stronger or weaker.

It tells you that the system has changed.

And in that system, OER is no longer peripheral.

It’s doing the work that abatement isn’t doing—yet.