The US will commit to halving its greenhouse gas emissions by 2030, Joe Biden is set to announce.
It comes as the US president prepares to host other world leaders, including Boris Johnson, at a virtual global climate summit held at the White House on Thursday.
The pledge – which amounts to nearly doubling previous commitments – and the summit represent a concerted US effort to reclaim credibility and leadership on climate change after four years of inaction under Donald Trump.
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Among measures which could be employed to reduce emissions by 50% to 52% are a “carbon border adjustment” – or carbon tariff – that would tax imports from countries that do not have similar emissions controls.
The White House could also target the biggest emitting sectors – including ensuring zero emissions from power plants by 2035, boosting energy efficiency in homes and businesses, incentives for electric vehicle use and expanding “carbon sinks” like forests and agriculture.
The target is based on 2005 levels of emissions.
A Biden administration official said: “We see multiple paths to reaching this goal.”
US Republicans say the target could damage the economy, with job cuts expected to come from areas such as power plants and the automotive industry, and they could oppose moves to lower the country’s dependence on gas, oil and coal.
Sector-specific goals will be revealed later in the year, but the administration has already moved to introduce a $2 trillion infrastructure plan, that could help Mr Biden deliver the emissions cuts he needs, including a clean energy standard.
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Prime Minister Boris Johnson will tell the gathering that 2021 will be the year for countries to “get serious” over climate change, having already announced that the UK will aim to cut its own emissions by 78% by 2035.
Mr Johnson is expected to tell the meeting: “The UK has shown that it’s possible to slash emissions while growing the economy, which makes the question of reaching net zero not so much technical as political.
“If we actually want to stop climate change, then this must be the year in which we get serious about doing so.
“Because the 2020s will be remembered either as the decade in which world leaders united to turn the tide, or as a failure.”
The UK will also host COP26 talks in Glasgow later in the year, and he will urge world leaders to attend.
China will also be in attendance at the summit, as will Canada, India and Brazil, with all nations under pressure to pledge more action on climate change, to ensure global warming does not go beyond the 1.5C goal.
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