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For one of her last acts as prime minister, Theresa May chose to address climate change.

On Wednesday, the outgoing U.K. leader is expected to pass into law legislation on a target to lower the U.K.’s emissions to “net-zero” by 2050, following advice earlier this year from the government’s Committee on Climate Change. The targets represent the most ambitious emissions benchmark set by any large, industrialized nation.

“Standing by is not an option,” said May in a release from her office late Tuesday evening. “Reaching net zero by 2050 is an ambitious target, but it is crucial that we achieve it to ensure we protect our planet for future generations.” The policy will also include a Youth Steering Committee on climate change, which will begin work in July, she said.

The target is more ambitious than the previous goal, which was to reduce emissions by 80% in 2050, from 1990 levels.

May is on her way out, and there are currently around a dozen MPs in the race to to replace her as Tory leader. However, the “net-zero” plan already has wide cross-political backing for months, even as Brexit has fractured political agreement on much else.

In May, the report from the Committee on Climate Change said the “net-zero” target was now possible at the same price as the previous goal, as renewable energy has become cheaper and more efficient.

That meant the U.K. should increase its commitments under the Paris Agreement, which obliges every member nation to commit to the most ambitious targets possible to keep global temperatures from rising less than two degrees from pre-industrial levels, the Committee said.

“Our report concluded that Net Zero is necessary, feasible and cost effective,” the Committee said in a statement following May’s announcement. “This is a major commitment for the coming decades, but we have highlighted the significant benefits of action. This step will send a strong signal to other countries to follow suit—and will help to drive the global effort to tackle climate change required by the Paris Agreement.”

Reaching that level is not simple, however. In May, the Committee laid out a widespread set of changes affecting not just industrial production and energy, but all sectors of British life, stipulating that Britons would have to eat less meat, use more efficient transport, and be more careful with their heating bills in order to meet the target.

The Committee also noted on Tuesday the shortcomings of the ambitious domestic targets: the “net-zero” goal does not yet include aviation and shipping, both of which are large sources of international emissions.

However, the U.K. has already had some notable success lowering domestic energy-related emissions. In 2017, emissions sunk as low as levels last seen in 1888, according to the International Energy Agency, driven by a greater share of low-carbon energy, particularly wind power, and lower coal use.

But worldwide, the trend has been going in the other direction: global emissions have continued to climb, breaking a fresh record last year, according to the IEA. That’s because the pace of renewable energy growth, while brisk, has not kept pace with growing demand fueled in part by the heating and cooling needed in extreme weather—a worrying “feedback loop.”

‘Standing By Is Not an Option:’ U.K. Is the First G7 Country to Commit to a ‘Net-Zero’ Emissions Target

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