On Wednesday, the U.S. formally withdrew from the Paris climate agreement, after President Trump first announced his plans to do so in 2017. The landmark climate agreement, a global pact to work to keep temperature rise below 2 degrees Celsius, has rules requiring three years to pass after its ratification before a country could withdraw. The Trump administration formally notified the United Nations of its decision one year ago, giving the required 12-month notice. Explaining the decision to exit last year, Secretary of State Mike Pompeo decried the "unfair economic burden imposed on American workers, businesses, and taxpayers by U.S. pledges made under the Agreement." The U.S. represents around 15% of global greenhouse gas emissions. Democratic presidential nominee Joe Biden has said he would re-join if elected.

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