All set for COP31? Read your sustainability report again.

Imagine a company executive at COP31, just finishing a presentation about the firm’s climate progress. A journalist raises a hand.

“You said you cut emissions by 30%. But your sustainability report says that figure covers only certain operations. What happened to the company's emissions overall?”

The exchange is hypothetical, but the problem is familiar. The number could be entirely accurate. The trouble starts when the sentence makes a broader promise than the data can support.

At previous climate summits, details like this have given journalists and campaigners stories that companies never intended to tell.

The official COP28 website offered visitors a “low-carbon” option. Turn it on and many of the images vanished, leaving a lighter-looking page.

But an ABC News investigation in October 2023 found that, in the original implementation, the hidden images were still being downloaded in the background. The energy savings were negligible.

Organisers changed the site after ABC News contacted them. Yet before the conference even opened, the website of the world's biggest climate summit had become the subject of greenwashing allegations.

The idea was meant to signal environmental care. What had not been adequately tested was whether the technology delivered what the label suggested. A straightforward technical check could have caught the problem before a reporter did.

When Coca-Cola was announced as a COP27 sponsor, the company stood to gain visibility at a major international climate conference. Environmental groups saw a different story: the company's contribution to plastic pollution.

In its 2022 brand audit, Break Free From Plastic reported Coca-Cola as the most frequently identified brand among the plastic waste collected by volunteers, for the fifth consecutive year. The audit did not measure all plastic waste worldwide, but it gave campaigners a concrete basis for challenging the sponsorship.

Coca-Cola had publicly stated goals on recycling and emissions reduction. Much of the coverage of its COP27 sponsorship, however, focused on its plastic footprint rather than those commitments.

A company can be very clear about why it is attending a COP and what it hopes to showcase. Journalists and civil society groups have no obligation to follow that agenda. What the company leaves out may become the story.

Ahead of COP28, independent research group Spendwell examined the climate commitments of 24 companies sponsoring the summit. Its 2023 analysis found that just one had a net-zero target validated under the Science Based Targets initiative (SBTi).

This did not mean that the other 23 companies were doing nothing about climate change. It showed something more specific, and harder to wave away: the gap between a public pledge and a target independently validated against a recognised standard.

The findings came from comparing public information. An outside researcher's work became a story in its own right, regardless of what the sponsors had chosen to highlight in their communications.

A manufacturer may have made real progress in cutting emissions per unit produced. But if output has risen sharply enough for absolute emissions to increase, the line “We have cut our emissions” invites a question the company may not want to face.

The same can happen with long-term targets. A company may have an ambitious net-zero pledge for 2050 while progress against its nearer-term milestones is slipping. Quoting only the distant goal might not be literally false, but it can leave a misleading impression of performance today.

Important qualifications have a habit of disappearing as technical reports are shortened into speeches and campaign copy. The apparently minor detail beside a headline number may be the very thing that makes the claim defensible.

There is little time left to rebuild an entire communications campaign. That may not be necessary. Start with the five most important climate claims your organisation intends to use at COP31 and return to the original evidence for each one.

Check what each figure actually measures. Compare the wording with earlier sustainability reports. If the calculation method or target has changed, make sure the person delivering the speech knows why.

Then ask a less comfortable question: where would a knowledgeable critic challenge this presentation, and what document would they cite?

It helps to have someone who did not write the material perform that check. After weeks working on the same deck, a team knows exactly what it meant to say. A fresh reader sees only what the words actually say.

Sometimes the fix is a single qualification. Sometimes the supporting evidence is too weak and the claim should be removed. A spokesperson needs to know not only the message, but also the questions it might invite.

COP31 will give companies a valuable opportunity to explain their climate work to an international audience. The experience of earlier summits suggests that even well-produced communications can come under scrutiny in ways the organisation did not anticipate.

The reports, targets and past statements a journalist would need to test your claims are probably already public.