This burning summer is the proof: the voices of climate denial aren’t just delusional, they’re deadly | Sadiq Khan

Europe is burning. This summer, an unprecedented series of heatwaves has swept through the continent and across many parts of the globe. The consequences have been nothing short of catastrophic. In recent weeks deadly blazes have torn through France, Greece and Spain, killing firefighters, forcing people from their homes and robbing them of their livelihoods.

With Tuesday marking Britain’s 34th day of temperatures exceeding 30C (86F) this year, the UK has also found itself reckoning with ferocious heat. Wildfires have forced evacuations in Suffolk and the Cairngorms. In London – where parks have become burnt, brittle and brown – hundreds of grass fires have put our firefighters under pressure like never before. In July, the weather station at Kew Gardens recorded its first ever month without rain since it started operating in 1871. As rivers run dry and reservoirs run low, farmers are warning of food shortages amid the deepening drought. With thousands of deaths already estimated to be linked to the extreme heat we saw in May and June alone, it’s likely this figure will climb higher still.

The terrifying scenes we’ve seen so far this summer are the latest part of a pernicious long-term pattern. This is the third drought London has experienced in the past five years. Across the world, the past 11 years have been the 11 hottest ever recorded – and with a super strength El Niño forming in the Pacific which could pour yet more fuel on the fire, that trend is all but certain to continue. The climate emergency is here – and no one can say they didn’t see it coming.

When I was first elected mayor back in 2016, I warned that our rapidly warming world would be the defining challenge of our time. I was the first mayor of a global city to declare a climate emergency. Since then, a coalition of climate deniers and delayers has been relentless in condemning the green policies I’ve introduced. When I announced my intention to expand the Ulez – creating the largest clean air zone in the world – they unsuccessfully attempted to drag down the debate and whip up a crude culture war. On social media, people were blinded by a dark blizzard of disinformation designed to discredit climate action. Radicalised by what he’d seen online, one man even detonated a homemade bomb, destroying a Ulez camera in a shocking act of domestic terrorism.

Looking back now, it feels like the fierce fight over Ulez marked the beginning of something else: a new age of extreme climate scepticism. In the years since, the horrifying reality of the climate crisis has come into sharp relief – and yet somehow the clamouring voices of denial and delay have grown louder than ever. Having dismissed climate change as a “con job”, Donald Trump has sought to sabotage global climate action, withdrawing the United States from the Paris agreement for the second time, cutting support for clean energy, and boosting oil and gas production. In the UK, where cross-party consensus on the climate crisis has collapsed, his ideas have been echoed by opposition politicians and rightwing populists who veer wildly between denialism and fatalism. As some claim the climate crisis is a hoax, others insist it’s too late to act.

Both arguments are bogus. The climate crisis is getting worse, but in London we’ve shown that – with courage and creativity – we can prepare ourselves for its impacts. We’ve planted more than 640,000 trees across the capital, shading our streets from the summer sun. We’ve embraced rewilding while creating and improving more than 2,000 football pitches’ worth of green space, providing natural drainage to prevent flooding. And just last month, we set out a plan to clean up our rivers and create safe swimming sites where Londoners can cool down in the heat. We have more zero-emission buses than any city in Europe and about a third of our country’s electric charging points.

At the same time, since I’ve been mayor our city’s carbon emissions have fallen by about a quarter, while our economy has continued to grow. And last year the Ulez helped us to get levels of nitrogen oxide – one of the most toxic pollutants in our air – within legal limits almost two centuries before experts predicted we would. Between 2019 and 2024, estimated deaths associated with air pollution in London fell by an estimated 40%.

Through C40 Cities, a network of almost 100 global cities I co-chair, London is working side by side with cities around the world to take on the climate emergency – from rolling out new green buses to boosting the supply of renewable energy – but we cannot do this alone. National governments across the globe must step up and meet the gravity of this moment with renewed focus, funding and resolve. This includes our own government, which should reassure the public by reaffirming its commitment to net zero and making clear that it will continue to reduce our reliance on oil and gas and to invest in green projects.

The most common refrain I hear from climate deniers is that green policies are some kind of luxury divorced from the worries of working people who are just trying to get by. But the idea that you can separate the climate crisis from the cost of living is patently absurd. What happens when droughts cause food prices to rise and when oil-price shocks squeeze household budgets? When hospitals are overwhelmed by vulnerable people struggling in the heat? When railways and roads buckle, workplaces close and schools are shuttered? The notion that climate action represents “woke nonsense” relies on the ridiculous premise that the climate crisis isn’t real – or that if it is, we won’t feel its impact on our lives. This year has proven just how wrong that is.

We are living in an era of extremes, and my fear is that – without urgent action – the worst is still to come. In this context, climate denial and delay isn’t just delusional – it’s deadly. Because it won’t be President Trump and the fossil fuel companies paying the price for failure – it will be the rest of us. If we are to protect our planet and the people who call it home, we must turn the tide on climate denial by preparing for a hotter future and embracing net zero like never before.