The UN secretary general has called on all countries to declare a climate emergency.
António Guterres was speaking at a virtual summit on the fifth anniversary of the Paris climate agreement,
He criticised rich countries for spending 50% more of their pandemic recovery cash on fossil fuels compared to low-carbon energy.
Over 70 world leaders are due to speak at the meeting organised by the UK, UN and France.
Mr Guterres said that 38 countries had already declared a climate emergency and he called on leaders worldwide to now do the same.
He said the emergency would only end when carbon neutrality was reached.
On the Covid recovery spending, he said that this is money being borrowed from future generations.
“We cannot use these resources to lock in policies that burden future generations with a mountain of debt on a broken planet,” he said.
The secretary general praised those countries who have come to today’s meeting with new targets and plans.
A number of big emitters, including Australia, Saudi Arabia, Russia and Mexico, are not taking part, as their climate actions were not deemed ambitious enough.
The UK has announced an end to support for overseas fossil fuel projects, and has today deposited a new climate plan with the UN.
It’s the first time that Britain has had to do this, as it was previously covered by the European Union’s climate commitments.
Today’s virtual gathering is taking place after the pandemic caused the postponement of the annual Conference of the Parties (COP) meeting, which had been due to take place in Glasgow this year.
UK Prime Minister Boris Johnson said the year was coming to an end with “a certain amount of scientific optimism” because “barely 12 months after the start of the pandemic, we’re seeing the vaccine going into the arms of the elderly”.
He added: “Together we can use scientific advances to protect our entire planet – our biosphere – against a challenge far worse, far more destructive even than the coronavirus. And by the promethean power of our invention, we can begin to defend the Earth against the disaster of global warming.”
The UK says that today’s short, action-oriented summit will put a premium on new commitments from countries.
Around 70 leaders from all over the world will take part, including the Secretary General of the United Nations, and President Macron of France. Pope Francis will also address the meeting.
The UK pointed to its new commitment on overseas fossil fuel projects as well as a new carbon cutting target of 68% by 2030, announced last week by the prime minister.
The EU also presented a new 2030 target of a 55% cut in emissions, agreed after all-night negotiations this week. “That is now Europe’s calling card,” said Ursula von der Leyen, President of the European Commission. “It is the go-ahead for scaling up climate action across our economy and society.”
China’s President Xi Jinping reiterated a previous commitment to reach peak CO2 emissions before 2030 and achieve carbon neutrality, where any emissions are balanced by removing an equivalent amount from the atmosphere, by 2060.
On Saturday, he announced that China would reduce its carbon emissions per unit of gross domestic product (GDP) by over 65% compared with 2005 levels. He said he would increase the share of non-fossil fuels in primary energy consumption by about 25%. And President Xi pledged to increase forest cover and boost wind and solar capacity.
Narendra Modi, the Prime Minister of India, said the country’s renewable energy capacity was on target to reach 175 Gigawatts by 2022, and it would aim to boost this to 450 Gigawatts by 2030. He added that the country had already reduced its carbon emissions intensity by 21% over 2005 levels and was on track to exceed the targets in the Paris Agreement.
Although President Donald Trump pulled the US out of the Paris pact, the summit saw statements from the Republican governor of Massachusetts, Charlie Baker and the Democrat governor of Michigan, Gretchen Whitmer, who said the US was “all-in” on tackling climate change.
Pope Francis said the Vatican had committed to reaching net zero emissions, similar to carbon neutrality, before 2050. “The time has come to change course. Let us not rob future generations of the hope for a better future,” he said.
Australia had held out the promise of not using old carbon credits to meet future cuts in emissions.
But the UK felt that this didn’t go far enough and the Australian Prime Minister Scott Morrison won’t be taking part.
Russia, South Africa and Saudi Arabia won’t be involved either.
Some observers believe this hard line is justified.
“From a kind of symbolic procedural point of view, it’s good to have everybody on board,” said Prof Heike Schroeder from the University of East Anglia.
“But from a proactive, creating some kind of sense of urgency approach it also makes sense to say we only get to hear from you if you have something new to say.”
Boris Johnson’s ebullient backing for tougher emissions cuts follows a tradition of British leadership on climate change.
UK experts play a central role on the Intergovernmental Panel on Climate Change, advising on science and policy.
In politics, the UK was an important player in negotiating the Rio framework convention on climate in 1992. And the deputy prime minister John Prescott pounded the table in the middle of the night to force through the Kyoto climate protocol in 1997.
The UK then passed its landmark Climate Change Act mandating step-by-step emissions cuts, and formed its Climate Change Committee to show how.
The UK strengthened the EU’s climate ambition. Then the Prince of Wales business leaders’ group convinced politicians that influential CEOs would support measures restricting CO2.
On economics, the 2006 UK Stern Review showed that ignoring climate change was more costly than tackling it.
And recently, the former Bank of England governor, Mark Carney, argued that banks should reject fossil fuel firms because they constitute an investment risk. No other country has a record quite like this.
The UK wants the focus to be on the countries who are set to make new net-zero announcements, or present new plans for 2030.
Boris Johnson said climate change was “already costing lives and livelihoods the world over, our actions as leaders must be driven not by timidity or caution, but by ambition on a truly grand scale.
“That is why the UK recently led the way with a bold new commitment to reduce emissions by at least 68% by 2030, and why I’m pleased to say today that the UK will end taxpayer support for fossil fuel projects overseas as soon as possible.”
The five years since the Paris agreement was adopted have been the warmest on record, according to the World Meteorological Organization (WMO), and emissions have continued to accrue in the atmosphere.
Over that period, many countries and businesses have started the process of decarbonisation.
The progress they’ve made now needs to be acknowledged and encouraged, says former UN climate chief Christiana Figueres.
“For this Saturday, they are focusing on the reduction of emissions, and that is a good thing because that progress that’s been seen in the real economy has to be reflected and incentivised further by those additional commitments.”
One area that’s unlikely to yield any progress at this meeting is the question of finance. Rich countries have promised to mobilise $100bn a year from 2020 under the Paris agreement – but the commitments on cash are just not forthcoming.
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