Activists and politicians have cautiously welcomed an unexpected statement from the US and China vowing to boost climate cooperation over the next decade.
The EU and UN described the move as encouraging and an important step, but Greenpeace said both countries needed to show greater commitment.
The US and China are the two largest CO2 emitters in the world.
They said they would work together to reach the 1.5°C temperature target set in the 2015 Paris Agreement.
The announcement by the two global rivals was made on Wednesday during the ongoing COP26 climate summit in Glasgow. US President Joe Biden and his Chinese counterpart Xi Jinping are expected to hold a virtual meeting as early as next week.
Scientists say limiting global temperature rise to 1.5°C will help humanity avoid the worst climate impacts. This is compared to pre-industrial temperatures.
In 2015, world leaders in Paris pledged to try to prevent the world from warming by more than 1.5 to 2 degrees through drastic emission reductions.
Commenting on the statement between the US and China, Genevieve Maricle, director of US climate policy action at WWF pressure group, said: “This announcement comes at a critical time during COP26 and offers new hope that, with the support and endorsement of two of the world’s most critical voices, we may be able to limit climate change to 1.5 degrees.
“But we also need to be clear about what remains to be done if the two countries are to achieve the necessary emissions reductions over the next nine years. 1.5C alignment requires a response from the entire economy.”
Greenpeace International Executive Director Jennifer Morgan also welcomed the statement, but warned that both countries needed to step up their efforts to achieve climate goals.
UN Secretary-General Antonio Guterres said the announcement was “an important step in the right direction”.
Frans Timmermans, head of EU climate policy, said it was “very encouraging” to see how China and the US are working together.
“It also shows that the US and China know that this topic transcends other issues. And it certainly helps us here at COP to come to an agreement,” he added.
Meanwhile, Kevin Rudd, former Australian Prime Minister and now president of the Asia Society, which works on global climate change agreements, told the BBC that the agreement was “not a game changer”, but still a big step forward.
“The current state of geopolitics between China and the United States is…awful, so the fact that you can now get this climate-specific cooperation agreement between Washington and Beijing is important momentum,” he said.
The statement between the US and China calls for increased efforts to close the “significant gap” left to reach that 1.5C target.
Steps have been agreed on a range of topics, including methane emissions, the clean energy transition and decarbonisation.
China’s chief climate negotiator Xie Zhenhua told reporters there is “more agreement between China and the US than divergence” on climate change.
Earlier this week, China refused to join an agreement to limit methane, a harmful greenhouse gas, but has instead pledged to develop a “national plan” to tackle the problem.
Mr. Xie was followed by John Kerry, the US climate envoy, who said that while the US and China had many disagreements, cooperation on climate is vital.
“Every step is important now and we have a long journey ahead of us,” he said.
China is the world’s largest emitter of carbon dioxide, followed by the US. In September, Mr Xi announced that China would aim for carbon neutrality by 2060, with a plan to reach peak emissions by 2030.
The US is aiming for net zero by 2050.
In other developments at Wednesday’s COP26 climate summit:
A draft of a final COP26 deal was announced, urging countries to strengthen their COP reduction targets by the end of 2022. The document also calls for more aid for vulnerable countries – but the text has been criticized by many for not being ambitious enough
British Prime Minister Boris Johnson urged other national leaders to give their negotiators more leverage to reach a final deal. At a press conference, he emphasized that the ambition to keep global temperature increases below 1.5°C was not yet dead
The sentiment was echoed by COP26 President Alok Sharma, who said: “We all know what is at stake in these negotiations and even the urgency of our task.” He also suggested that “near-final texts” on an agreement could be published overnight before the groups meet again tomorrow, ahead of the intended final day of the conference on Friday.
The focus of COP26 on Wednesday was travel. Dozens of countries have pledged to phase out petrol and diesel cars, but the US, China and Germany have not signed up. A number of major manufacturers – including Ford and Mercedes – have also made commitments.
COP26 climate summit – The basics
Climate change is one of the world’s most pressing problems. Governments must pledge more ambitious cuts to gas warming if we are to avoid larger global temperature rises.
The summit in Glasgow is where change could take place. You have to pay attention to the promises of the world’s biggest polluters, such as the US and China, and whether poorer countries are getting the support they need.
All our lives will change. Decisions made here can affect our jobs, how we heat our homes, what we eat and how we travel.
What does climate change look like for you?
Will the UK meet its climate targets?
How extreme weather is linked to climate change
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