Canada and fellow G20 countries set to agree to limit global warming to 1.5 C, according to draft

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The world's 20 richest countries will commit this weekend to tackling the existential threat of climate change, paving the way for more detailed action at a United Nations climate change summit next week, according to a draft communique seen by Reuters.  

Leaders of Group of 20, who gather for talks on Saturday and Sunday in Rome, will pledge to take urgent steps to reach the goal of limiting global warming to 1.5 C, according to the draft.

They will then head to Glasgow, Scotland for a crucial United Nations gathering of almost 200 countries, known as COP26.

The Conference of Parties (COP), as it's known, meets every year and is the global decision-making body set up in the early 1990s to implement the United Nations Framework Convention on Climate Change and subsequent climate agreements.

The landmark 2015 Paris agreement committed signatories to keeping global warming to "well below" two degrees above pre-industrial levels, and preferably to 1.5 degrees.

Since then, as extreme weather episodes have intensified and carbon levels in the atmosphere have grown, climate scientists have increasingly emphasized the importance of a 1.5-degree cap to limit the risk of environmental catastrophe.

"Responding to the call of the scientific community, noting the alarming reports of the IPCC [Intergovernmental Panel on Climate Change] and mindful of our leadership role, we commit to tackle the existential challenge of climate change," said the draft, which might still be changed.

"We recognize that the impacts of climate change at 1.5 degrees are much lower than at two degrees and that immediate action must be taken to keep 1.5 degrees within reach," the G20 said.

"We acknowledge the key relevance of achieving global net zero greenhouse gas emissions or carbon neutrality by 2050," the statement said, referring to a recommendation by UN climate experts who say the mid-century deadline is crucial to meet the 1.5-degree warming limit.

However, the 2050 date appears in the draft in brackets, indicating it is still subject to negotiation.

Some of the world's biggest polluters say they cannot reach the 2050 target date, with China, by far the largest carbon emitter, aiming for 2060.

The G20 bloc, which also includes Brazil, China, India, Germany and the United States, accounts for more than 80 per cent of the world's gross domestic product, 60 per cent of its population and an estimated 80 per cent of global greenhouse gas emissions.

The G20 reaffirmed a commitment to "phase out and rationalize" fossil fuel subsidies by 2025 and to curb coal power, considered a principal culprit of global warming.