The striking feature of the international climate change conference is the pledge by America to cut its carbon emissions by 50-52 per cent below 2005 levels by the year 2030. Sixteen years after that frightful level was reached by the generally impervious developed countries, Thursday’s commitment on carbon emissions can be contextualised with President Joe Biden’s appeal to participating nations to help “overcome the existential crisis of our time as we are in a decisive decade for tackling climate change”.

There may be hope yet as President Xi Jinping is in attendance and not the least because China, along with America, is one of the major polluters. The USA’s new target, which was unveiled on Thursday at a virtual summit of 40 global leaders, essentially doubles the previous promise. Leaders of India and China, two of the world’s biggest emitters, made no new commitments.

“Scientists tell us that this is the decisive decade; this is the decade we must make decisions that will avoid the worst consequences of the climate crisis,” President Biden said at the summit’s opening address. And then the reality adressed to the comity of nations ~ “We must try to keep the Earth’s temperature to an increase of 1.5C. The world beyond 1.5 degrees means more frequent and intense fires, floods, droughts, heatwaves and hurricanes ~ tearing through communities, ripping away lives and livelihoods.”

He said there was a moral and economic imperative to immediately act on climate change. Referring to America’s new carbon-cutting pledge, President Biden added: “The signs are unmistakable, the science is undeniable, and the cost of inaction keeps mounting. The US isn’t waiting, we are resolving to take action.”

President Biden’s performance, as refreshing as it was robust, follows four years of negligent nonchalance on the part of Donald Trump. Climate activist Greta Thunberg, who was testifying before Congress on Thursday, challenged world leaders to do more on the climate crisis. The UK is playing a critical role this year as president of the crucial COP26 later this year. The government is tasked with achieving agreement in Glasgow when world leaders meet there in November.

In his virtual conference address, Prime Minister Boris Johnson assured global leaders that tackling climate change was “not bunny-hugging”. At the summit, Mr Johnson called President Biden’s announcement about cutting US greenhouse gas emissions “game-changing”.

“We can do this together across the world. It’s going to mean the richest nations coming together and exceeding the $100 billion commitment they already made in 2009,” he said. The Biden administration has been riveted to climate change ever since the inaugural on 20 January. The pledge to go beyond a 50 per cent cut will be welcomed by scientists and campaigners. The future of the world hinges on the fulfilment of Joe Biden’s pledge.