A crucial U.N. conference heard calls on its first day for the world's major economies to stick to promises of financial help to address the climate crisis, while big polluters India and Brazil made new pledges to cut emissions.
World leaders, environmental experts and activists all pleaded for decisive action to halt the global warming that threatens the future of the planet at Monday's start of the two-week COP26 summit in the Scottish city of Glasgow.
The task was made even more daunting by the failure of the Group of 20 major industrial nations to agree to ambitious new commitments over the weekend in Rome.
The G-20 is responsible for around 80% of global greenhouse gases and a similar proportion of carbon dioxide, the gas produced by burning fossil fuels that is the main cause of the rise in global temperatures, which are triggering an increasing intensity of heatwaves, droughts, floods and storms.
"Humanity has long since run down the clock on climate change. It's one minute to midnight on that Doomsday clock and we need to act now," British Prime Minister Boris Johnson told the opening ceremony.
Delayed by a year because of the COVID-19 pandemic, COP26 aims to keep alive a target of capping global warming at 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels.
To do that, it needs to secure more ambitious pledges to reduce emissions, lock in billions in climate financing for developing countries, and finish the rules for implementing the 2015 Paris Agreement, signed by nearly 200 countries.
The pledges made so far to cut emissions would allow the planet's average surface temperature to rise 2.7 degrees Celsius this century, which the United Nations says would supercharge the destruction that climate change is already causing.
‘Time for action’
Addressing the summit, Britain's Queen Elizabeth said that "the time for words has now moved to the time for action," as she urged world leaders to think of future generations when negotiating a deal to limit global warming.
The 95-year-old was due to attend the event in person in Glasgow but delivered a recorded video after doctors advised her to rest for two weeks.
"It is the hope of many that the legacy of this summit – written in history books yet to be printed – will describe you as the leaders who did not pass up the opportunity; and that you answered the call of those future generations," said Elizabeth, the world's oldest and longest-reigning monarch.
"That you left this conference as a community of nations with a determination, a desire, and a plan, to address the impact of climate change; and to recognize that the time for words has now moved to the time for action."
The queen paid tribute to her late husband, Prince Philip, who died aged 99 earlier this year. She recalled how he had warned an academic gathering in 1969 about the need to tackle the threats from pollution.
"If the world pollution situation is not critical at the moment, it is as certain as anything can be that the situation will become increasingly intolerable within a very short time," she quoted him as saying.
The queen said she was particularly happy to welcome leaders to the summit because "the impact of the environment on human progress" was a subject close to his heart.
Elizabeth added she "could not be more proud" that his work had been continued by her two closest heirs, Prince Charles and Prince William, who are both attending the summit.
U.N. Secretary-General Antonio Guterres reminded delegates that the six hottest years on record have occurred since 2015.
Other speakers, including activists from the poorer countries hardest hit by climate change, had a defiant message.
"Pacific youth have rallied behind the cry 'We are not drowning, we are fighting'," said Brianna Fruean from the Polynesian island state of Samoa, at risk from rising sea levels. "This is our warrior cry to the world."
Leaders of countries such as Kenya, Bangladesh, Barbados and Malawi called rich nations to task for failing to deliver promised financial help to deal with climate change.
"The money pledge to least developed nations by developed nations ... is not a donation, but a cleaning fee," Malawi's President Lazarus Mccarthy Chakwera said.
"Neither Africa in general, nor Malawi in particular, will take 'no' for an answer. Not any more."
President Xi Jinping of China, by far the biggest emitter of greenhouse gases, told the conference in a written statement that developed countries should not only do more but also support developing countries to do better.
Big hitters stay home
Xi's absence, along with that of Russia's Vladimir Putin, president of one of the world's top three oil producers along with the United States and Saudi Arabia, may hinder progress.
Swedish activist Greta Thunberg tweeted an appeal for her millions of supporters to sign an open letter accusing leaders of betrayal.
"This is not a drill. It's code red for the Earth," it read. "Millions will suffer as our planet is devastated – a terrifying future that will be created, or avoided, by the decisions you make. You have the power to decide."
India and Brazil, two of the world's largest polluters, both used the platform to provide new emission cutting pledges.
"We will act responsibly and search for real solutions for an urgent transition," Brazilian President Jair Bolsonaro, who has presided over more than two years of soaring deforestation in the Amazon rainforest, said.
Brazil said it would cut its greenhouse gas emissions by 50% by 2030, compared to a previous pledge of 43% in that period.
However, the cuts are calculated against emissions levels in 2005, a baseline which was retroactively revised last year, making it easier for Brazil's targets to be met.
Prime Minister Narendra Modi set 2070 as a target for India to reach net-zero carbon emissions, much later than those set by other polluters and twenty years beyond the U.N.'s global recommendations.
In Rome, the G-20 failed to commit to the 2050 target to halt net carbon emissions, undermining one of COP26's main aims.
Instead, they only recognized "the key relevance" of doing so "by or around mid-century," and set no timetable for phasing out domestic coal power, a major cause of carbon emissions.
The commitment to phase out fossil fuel subsidies "over the medium term" echoed wording they used as long ago as 2009.
'Calamitous threats'
Discord among some of the world's biggest emitters about how to cut back on coal, oil and gas will make progress difficult in Glasgow, as will the rich world's failure to keep its promises.
In 2009, the developed countries most responsible for global warming pledged to provide $100 billion per year by 2020 to help developing nations deal with its consequences.
The commitment has still not been met, generating mistrust and a reluctance among some developing nations to accelerate their emissions reductions.
Barbados Prime Minister Mia Mottley compared the vast sums pumped into the global economy by rich countries' central banks in recent years with those spent on climate help.
"Our people are watching and our people are taking note ... Can there be peace and prosperity if one-third of the world lives in prosperity and two-thirds lives under seas and face calamitous threats to our well-being?" she said.
Developed countries confirmed last week they would be three years late in meeting the $100 billion climate finance pledge – which many poor countries and activists say is insufficient anyway.
U.S. President Joe Biden said the rich must do more, admitting that "right now we're falling short," while French President Emmanuel Macron also called on all developed countries to deliver their fair share of climate funding.
Txai Surui, a 24-year-old indigenous youth leader from the Amazon rainforest, said too much damage had already been done.
"The animals are disappearing, the rivers are dying and our plants don't flower like they did before. The Earth is speaking. She tells us that we have no more time."