Trump ended his presidency with an exhausting cacophony of carnage.

An apt end to four years in which he unnerved, ensnared and bewildered. His was an administration of norm-breaking chaos. Among the most damaging blows inflicted during the Trump era were the litany of regulatory rollbacks that were designed to weaken rules designed to protect the environment.

But Trump is gone. And the world might be on the verge of a green revolution.

The freshly inaugurated President Biden was elected on the most ambitious climate platform ever put forward by a presidential candidate. He is moving quickly and executing his climate change agenda through ambitious executive action.

And then there’s the pandemic. It has compelled us to live drastically different lives and triggered the biggest carbon crash ever recorded. Sure, the relief for the environment was short-lived — we’re already back to pre-pandemic levels — but the crisis has given climate campaigners a relatable comparison to help them frame the argument for urgent climate action.

Revolutions are often born out of crises. A global survey by Ipsos found that over 70% of respondents across the world believe that climate is as serious a crisis as Covid-19.

But climate change is a planetary-scale threat and, as such, requires planetary-scale reforms. The government’s long-awaited plan to start a green industrial revolution — a central part of its ambition to ‘build back better’ — is a good start. And there are some promising signs from industry. A number of large firms wrote to the UK government, prompting them to make the Covid-19 recovery green. Britain’s biggest brands have promised to look inwards and take urgent action on the climate crisis

And when they do, naturally they’ll want to brag about it — whether it’s above the line or below the line, 2021 will be the year that the world’s biggest brands wax lyrical about how they are walking the sustainability line.

But they’ve got to be careful.

Pre-pandemic, GlobalWebIndex documented a large degree of scepticism towards the sustainability stance of big brands, with 49% of the belief that brands just “say what society wants to hear” on climate change. And who can blame them? Many of the world’s biggest brands have a long and shameful track record of greenwashing: doing as little as possible to fix their sustainability issues, while simultaneously exaggerating and demanding credit for their pitiful efforts.

Brands preaching their environmental virtues has the potential to be inspiring, but it can also be incredibly annoying. Worse still, it can be damaging. To strike the right balance, here are five things that every brand communicator needs to bear in mind:

Many brands greenwash by grounding their sustainability communications in irrelevance, focusing on a zeitgeist issue like ‘ocean plastics’ when it has nothing to do with the problems they cause. The environmental challenges faced by industries are well-documented and clear. You must tackle yours head-on and avoid token initiatives.

Here today, gone tomorrow’ sustainability initiatives conceived for the sole purpose of advertising ring hollow and are very easy to spot. If you’re going to talk about sustainability, anchor your communications in credible and robust actions that your business is taking — if that leaves you with an uninspiring story, you’re not doing enough.

Greenwashing is most insidious when brands take a problem caused by their industry and put all the responsibility on the general public to fix it. If you are going to encourage the public to play their part, you must be doing your much larger part too.

No one brand can fix everything and save the world, the climate problem is too vast, and the public knows it. Your sustainability communications must be realistic when stating the impact of your actions and initiatives.

Even if you’re doing well, don’t preach perfection, that’ll make people suspicious. Spell out how your efforts can be better. You must be transparent about your targets, realistic about why they matter and clear on when and how you will achieve them.

The quality of a company’s communication on sustainability and its ability to strike the right tone will increasingly become a competitive advantage. Now is the time to be bold, look inward and give an authentic account of how your brand is raising to the challenge of the most important fight of our generation.