Governments are facing increasing pressure to rapidly scale up action on global warming.

The pressure builds as a new report from the United Nations warns that humans are having an “unequivocal” impact on the climate.

The latest global review from the Intergovernmental Panel on Climate Change (IPCC) said the world will reach or exceed temperature rises of 1.5C – seen as a threshold beyond which the worst impacts of global warming will be felt – over the next two decades.

Without quick wide reaching action to reduce greenhouse gas emissions, temperature rises in the 21st century will exceed both the 1.5C and a higher, riskier 2C warming limit agreed to by countries in the international Paris climate treaty, it found.

Responding to the report, UN secretary general Antonio Guterres said it was a “code red for humanity”.

He warned: “The alarm bells are deafening, and the evidence is irrefutable: greenhouse gas emissions from fossil fuel burning and deforestation are choking our planet and putting billions of people at immediate risk.

“Global heating is affecting every region on Earth, with many of the changes becoming irreversible.

“The internationally agreed threshold of 1.5C is perilously close.”

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He urged countries to urgently step up efforts and set out national plans for cutting emissions this decade ahead of a crucial UN climate summit taking place in Glasgow in November.

He called for an end to coal-fired power plants and fossil fuel exploration, a shift to renewable energy and funding to protect vulnerable communities, and said the Covid recovery must be in line with climate goals.

As the report was published, UK Prime Minister Boris Johnson said it was clear the next decade was going to be pivotal to securing the future of the planet.

“We know what must be done to limit global warming – consign coal to history and shift to clean energy sources, protect nature and provide climate finance for countries on the frontline.”

The prime minister, whose government is due to publish its strategy on cutting UK emissions to zero overall by mid-century this autumn, added: “The UK is leading the way, decarbonising our economy faster than any country in the G20 over the last two decades.

“I hope today’s IPCC report will be a wake-up call for the world to take action now, before we meet in Glasgow in November for the critical Cop26 summit.”

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With the UK hosting the Cop26 summit, UK government minister and Cop26 president, Alok Sharma said: “The science is clear, the impacts of the climate crisis can be seen around the world and if we don’t act now, we will continue to see the worst effects impact lives, livelihoods and natural habitats.

“Our message to every country, government, business and part of society is simple. The next decade is decisive, follow the science and embrace your responsibility to keep the goal of 1.5C alive.”

He called on countries to come forward with ambitious 2030 emissions reduction targets and long-term strategies with a pathway to net zero by the middle of the century.

Governments need to take immediate action to end coal power, accelerate the rollout of electric vehicles, tackle deforestation and reduce methane emissions, he urged.

Despite talking a strong game, the UK Government is itself facing calls for more action.

Labour's shadow business secretary Ed Miliband warned that the report highlighted what recent floods, heatwaves and wildfires were also showing, that “climate breakdown has already begun, that it’s accelerating across the globe”.

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He said the case for transformative action to reduce emissions was not only the overwhelming moral choice, but the only sensible prudent economic course.

“The biggest threat we now face is not climate denial but climate delay including from the UK Government," said Mr Miliband.

“The scene is now set for Cop26, our last, best hope of a global breakthrough to limit temperature rises to 1.5 degrees.

“The message to the Government here and those around the world is enough rhetoric, enough delay – the era of action is now.”

Campaigners also seized on the report to urge the UK Government to do more to reduce emissions.

Jake Woodier, from The Climate Coalition, which includes groups ranging from the National Trust and the Women’s Institute to WWF, Oxfam and the RSPB, said: “Climate change is already here, and after a summer of chaotic and destructive weather, the public want Boris Johnson’s government to act decisively.

“We already know what’s needed to secure a safer future: from saying no to polluting fossil fuels like the Cambo oil field, to restoring the natural world, protecting forests and meeting financial promises to support people on the frontline of the climate crisis.

“Now, it’s time to get on and do it."

Professor Joanna Haigh, from Imperial College London, said: “The window is still open for governments to avoid the worst impacts and risks and to secure a strong outcome at Cop26 just three months away – but this will depend on nations coming forward ahead of the summit to put in place robust emission reduction plans for the next decade.

“This window won’t remain open for much longer."

In Wales, the Government declared a climate emergency in 2019, pledging to put climate consideration at the centre of all its decision making. 

Following May's election, a climate super ministry was created within the Government that will contain interrelated departments such as transport, environment and housing.

In June, the Government froze all future road-building plans, with deputy climate minister Lee Waters saying: "If we carry on going as we're going, we're not going to hit net zero until 2090.

"At the very latest scientists tell us we have until 2050 to stop this running out of control."

*Additional reporting by PA

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