Global temperatures could reach an irreversible tipping point in just 12 years if the world doesn't act dramatically to reduce the amount of carbon dioxide released into the atmosphere, scientists warned in a new report.

科学家们在一份新报告中警告称，如果不采取行动大幅减少排放到大气中的二氧化碳量，全球气温可能在12年内达到一个不可逆转的临界点。

The dire¹ assessment² puts the spotlight³ on President Donald Trump⁴ and the Republican-controlled Congress.

这一可怕的预测将人们的注意力集中在唐纳德·特朗普总统和共和党控制的国会上。

Trump and many of his most ardent⁵ supporters in Congress have questioned man-made climate change and the president could remain in office for nearly half the time the scientists say is crucial for action.

特朗普和他的众多支持者对人为造成气候变化提出了质疑，而科学家们表示，在采取保护地球行动的关键时刻，特朗普可能会浪费一半的时间。

The United Nations panel on climate change says the impact of climate change can still be slowed down if countries around the world take unprecedented⁶ action to reduce their use of fossil fuels and release less carbon dioxide and other greenhouse gases into the air.

联合国气候变化委员会表示，如果世界各国采取前所未有的行动，减少化石燃料的使用，减少二氧化碳和其他温室气体的排放，那么气候变化的影响仍然可以减缓。

But the United States government has not supported aggressive climate policies under the Trump administration.

但在特朗普执政期间，美国政府并不支持保护地球气候政策。

President Trump decided⁷ to withdraw the U.S. from the Paris Climate Agreement -- an accord where countries pledged to drastically reduce greenhouse gas emissions⁸.

特朗普总统决定让美国退出各国承诺大幅减少温室气体排放的《巴黎气候协定》。

The current administration has moved to roll back most of the climate-oriented policies proposed by the Obama administration, proposing replacements⁹ in some cases which experts said won't go as far toward reducing emissions.

目前的美国政府已经采取行动，取消了奥巴马政府提出的大部分以保护地球气候为导向的政策，甚至提出了替代方案，不过专家们称，这些方案在减少温室气体排放方面不会起到多大作用。

The Environmental Protection Agency declined to comment on the UN report's findings.

美国环境保护署日前拒绝就联合国报告的调查结果予以评论。

The UN panel's researchers found that "human caused" carbon dioxide emissions need to be cut by nearly half of 2010 levels by 2030 to stave off the worst effects of climate change.

联合国小组的研究人员表示，到2030年，人为活动产生的二氧化碳排放量需要减少近一半，以避免气候变化带来最严重的影响。

Scientists said "rapid, far-reaching and unprecedented changes in all aspects of society" are required to limit the possibility of irreversible environmental damage.

科学家们表示，现在需要“社会各方采取迅速、有效和空前的措施”来限制不可逆转的环境破坏的可能性。