The Observer view on climate change protesters: their voice must be heard

For decades, we have faced an incontrovertible truth: that human lifestyles are risking the future habitability of our planet. For decades, political leaders have invoked rousing rhetoric in the face of this challenge while failing to act to avert catastrophe. Climate change is an existential risk to the future and the window available to prevent disastrous overheating is closing rapidly.

Only now, almost 30 years after the International Panel on Climate Change published its first report setting out the scientific evidence, is there any sense that something may be shifting in popular and political perceptions. Extinction Rebellion protesters have brought parts of central London to a standstill, their action coming in the wake of the school climate strikes, when more than 1.4 million young people took part globally. For his part, the governor of the Bank of England, Mark Carney, warned the financial sector last week that it must take the threat seriously, framing the argument in terms that it understands best: that in a heated world there is a real risk to profit margins.

These are different responses to the same hard facts. The 20 warmest years since records began occurred in the past 22 years and the IPCC estimates we are likely to reach 1.5C above temperatures in pre-industrial times as early as 2030 on current trends. If we are to have any chance of keeping global warming to well below 2C, as set out in the Paris agreement, the world needs to reach net zero-carbon emissions by the middle of this century. The UN secretary general has warned that we have one year to change course to avoid missing this target.

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The need for action is critical. The rate at which the world is warming is rapidly increasing and scientists fear we will soon reach a tipping point. One example would be the disappearance of Arctic sea ice in summer, an event that would impair Earth’s ability to reflect solar radiation and lead to even more warming and devastation. Global warming is already inflicting huge damage. We are seeing more extreme weather events – heatwaves, floods and droughts – with increasing cost to human, animal and plant life. Scientists believe 8% of the world’s species are at risk of extinction. A quarter of the world’s coral reefs have already died as a result of the warming of our oceans.

It will be the world’s poorest nations that will bear the brunt of the devastation to come, even though they have the least responsibility – they have made a negligible contribution to historic emissions, and the poorest half of the world is responsible for just 10% of annual emissions. Yet the consequences will continue to fall on these underprivileged countries.

However, there has been some progress. Carbon emissions are falling in many countries; in the UK, they have been cut to 19th-century levels. But these reductions have not come quickly enough and what has been achieved so far has been the gathering of the low-hanging fruit, such as closing coal-fired power stations, changes that have not required big lifestyle alterations.

Since 2015 the British government has performed a series of dizzying U-turns on climate change policy, sacrificing commitments such as zero-carbon homes and investment in carbon capture storage on the altar of austerity. Now Brexit is distracting us even more from the impending crisis. As a result, the UK is on course to decisively miss its own legally binding emissions targets for 2027 and 2032. Internationally, the election of President Trump has seen the United States withdraw from the Paris agreement, and the election of rightwing populists such as Jair Bolsonaro of Brazil poses a further threat to global progress.

The ratcheting up of the discourse reflects the ratcheting up of the stakes. Extinction Rebellion is a movement born of desperation, showcasing the determination of activists to use whatever peaceful tactics are necessary to get politicians to take the threat seriously. They enjoyed real success last week, forcing climate change into the headlines when it would otherwise have been ignored.

But there are limits to the effectiveness of this approach. Limiting global warming requires widespread lifestyle change among the world’s richest populations. Proposals for a green new deal developed on both sides of the Atlantic illustrate how much government can do with political commitment. But action is far more likely if voters are applying pressure on government to take the radical action that will shift people’s lifestyles and behaviour – through measures such as green taxation, regulation or even rationing.

So while a radical movement such as Extinction Rebellion can act as a much-needed catalyst to get people talking about climate change, the case for action will in the end need to be made in a much broader way that appeals to voters from across the political spectrum. There’s much to learn from the campaign for equal marriage in the US, which successfully won round conservative voters by framing the argument not primarily in the language of rights, but in values of love, commitment and family.

This remains the missing link in avoiding catastrophic climate change. How to make people see that this is the most existential threat humankind has ever faced, yet without making them feel fatalistic about their lack of ability to influence events. If we fail to crack this conundrum, the future of our planet hangs in the balance.