Last week Greta Thunberg and 20 other young climate activists demanded that world leaders gathering at Davos at the end of the month abandon fossil fuels. While no thinking human being could disagree with them, I find myself increasingly worried about the unthinking ageism that has crept into this movement.

Greta Thunberg: At Davos we will tell world leaders to abandon the fossil fuel economy Read more

“Young people are being let down by old people and those in power,” they declared, as though the fact that the most powerful people are old means that most old people are powerful. Clearly, they aren’t. In reality, swaths of older people have neither money nor influence, and also support the school climate strikes.

What’s happening here, I think, is that some young climate activists have adopted the intergenerational unfairness narrative – the one that also blames old people for zero-hours jobs, soaring house prices and pretty much everything else that’s bad, apart from the overconsumption of avocados.

It’s the “OK, boomer” retort now applied to the climate, as expressed last month by the singer Billie Eilish: “Hopefully the adults and the old people start listening to us [about climate change]. Old people are gonna die, and don’t really care if we die, but we don’t wanna die yet.”

But stereotyping old people as “après moi, le déluge” types who don’t give a fig about what happens to the planet after they leave it is nonsense. The majority of parents and grandparents are deeply concerned about what they leave behind for their families. (And let’s not be parentist about it, as if only those with offspring care about the planet. Indeed, there are plenty of older people who chose not to have children because of their concern for the planet.)

The novelist Chimamanda Ngozi Adichie has warned of the dangers of the single story about another person or country, arguing that our lives are made up of many overlapping stories. “The single story creates stereotypes, and the problem with stereotypes is not that they are untrue, but that they are incomplete. They make one story become the only story,” she argued. This is what the youth climate narrative risks doing.

Play Video 0:50 'It's nice to meet you': Greta Thunberg and David Attenborough speak over Skype – video

Young climate activists have first-hand experience of ageism, having been admonished repeatedly (mostly by – yes! – old, white men) that they’re too young to know what they’re talking about. It would be a pity if they just flipped this over to stereotype older people. Indeed, over-65s grew up in pre-throwaway times and know all about keeping, repairing and reusing; we need those skills now more than ever.

They also have the freedom to imagine a better world: as the radical American anti-ageism campaigner Maggie Kuhn pointed out: “We the elders should be society’s futurists … we have nothing to lose.”

Of course the single story makes good copy, and some youth climate strikers, such as Jamie Margolin, co-founder of the youth climate justice movement Zero Hour, in her admirable Ted Talk, are much more nuanced in their analysis. In reality, it’s not generations but structures of power and domination, systems of extraction and exploitation of people and planet for profit, that have brought us to this point of peril. Thunberg recognises this when she eloquently attacks the idea of untrammelled economic growth.

Polarising old and young isn’t an effective long-term strategy. If climate activism is to stand any chance of succeeding, it needs to be intergenerational and multigenerational, based on the idea of stewardship of the commons – those resources shared by us all that we need to safeguard for future generations. That way we can be sure future generations will actually exist.

• Anne Karpf is the author of How to Age, and professor of life writing and culture at London Metropolitan University