In a warning to countries’ lagging behind in the transition required to achieve net-zero carbon emissions, he said urgent progress in the battle to reverse the drastic effects of climate change was crucial if goals were to be met.
US President Joe Biden’s special envoy for climate praised the “great successes” of Cop26 but said the 65 per cent of the world’s countries that made commitments need to quicken action.
“This year we have to implement those promises and what it means is that we have to decarbonise the power sector five times faster that we are right now," Mr Kerry told the Net Zero Delivery Summit in London on Wednesday.
"We have to deploy renewables five time faster than we are right now, we have to transition to electric vehicles about 20 times faster than we are now, and we have to fully transition to a resilient net-zero economy faster.”
Slashing methane emissions, stopping deforestation and keeping the key Paris Agreement pledge, to limit global warming to 1.5°C above pre-industrial levels, were among the key commitments made at Cop26 in Glasgow, Scotland last November.
Mr Kerry, a former US secretary of state, said more must also be done to bring nations that have not made commitments to the table in the global fight.
In his speech at the event in Mansion House, central London, he criticised climate change sceptics, saying “you can’t be half pregnant on the issue of climate”.
“If you accept the science that this blanket is warming the Earth and we’re making it worse every single day, that’s been science that we’ve been hearing about for 30 years.”
Mark Carney, the UN special envoy on climate action and finance and co-chair of the Glasgow Financial Alliance for Net Zero warned the same meeting the world was “caught in a timidity trap, dithering our way towards climate disaster”. On the rising energy bills and the effects the Ukraine war has had on the supply and flow of energy, Mr Carney said: “The shock of this energy crisis must prompt a comprehensive response and if the world truly wants revolution towards a more sustainable, resilient and fair energy system the finance for it will be there.”
Mr Kerry pointed to the International Energy Agency’s assessment that if the Cop26 pledges were met in full, it would hold the global rise in temperatures to 1.8°C by 2100.
He said the countries engaged in the race to reverse climate change are not “in the realm of impossibility”.
“We can win this battle but we have to do more and that’s the new reality of what we have to face up to,” Mr Kerry said. "We are not where we need to be, we are not moving fast enough.
"For an issue which is existential as leader after leader now appropriately calls it, we are not behaving in a way that reflects that existentiality.”
Mr Carney warned there could be no energy security without sustainable sources and clean energy. “The folly of our lean, fossil fuel-based global energy system has once again been laid bare,” Mr Carney told the summit, while adding there was no escaping the fact that “some limited and targeted” investment in fossil fuels is crucial to a smooth transition to cleaner energy.
The former Bank of England governor said that change was not simply “flipping a green switch”.
Mr Carney said finance would not by itself drive the transition to net zero, but the sector was a catalyst to speed up what companies and governments initiate.
“Transition means transition,” he said. “Financial institutions must go to where the emissions are and back those companies, including those in the heavy emitting sectors like steel, cement and transport, that have credible plans to transform their businesses for a net-zero world.”
He said now was a “critical time” for changes to be made as halfway between Cop26 and Cop27, the summit scheduled to take place in Sharm El Sheikh in Egypt in November before the COP28 meeting in Abu Dhabi.