科学家警告说，可能引发全球危机的临界点现在正在发挥作用

科学家警告说，可能引发全球危机的临界点现在正在发挥作用

Several active 'tipping points' of irreversible change in the world's climate system threaten to unleash a global cascade of events that amounts to a planetary emergency, scientists warn.

科学家们警告说，全球气候系统发生不可逆转变化的几个活跃的“临界点”有可能引发一系列全球性事件，导致全球进入紧急状态。

The concept of tipping points was introduced by the Intergovernmental Panel on Climate Change (IPCC) just over 20 years ago, but researchers now warn that already nine of these vulnerable environmental thresholds are in very real danger of being breached – and much sooner than was ever anticipated.

“临界点”的概念是政府间气候变化专门委员会(IPCC)在20多年前提出的，但研究人员现在警告说，在这些脆弱的环境临界点中，已经有9个面临被突破的真正危险——而且比预期的要早得多。

A decade ago we identified a suite of potential tipping points in the Earth system, now we see evidence that over half of them have been activated, says climate system researcher Tim Lenton from the University of Exeter in the UK.

英国埃克塞特大学的气候系统研究员蒂姆·莱顿说:“十年前，我们确定了地球系统中的一系列潜在临界点，现在我们看到的证据表明，超过一半的临界点已经被激活。”

The growing threat of rapid, irreversible changes means it is no longer responsible to wait and see. The situation is urgent and we need an emergency response.

“快速、不可逆转的变化带来的日益严重的威胁意味着，我们不再有责任坐视不管。情况紧急，我们需要紧急应对。”

In a new research comment, Lenton and an international team of climate scientists warn that these tipping points – which many assumed were low-probability risks that might only be dangerous if global temperatures rose 5°C above pre-industrial levels – are in fact becoming exceeded at increases of 1–2°C.

在一项新的研究发表评论,莱顿和一个国际气候科学家小组警告说,这些临界点——许多人认为是低概率的风险,可能只有危险如果全球气温上升5°C高于工业化前的水平——事实上成为超过增加1 - 2°C。

We think that several cryosphere tipping points are dangerously close, but mitigating greenhouse-gas emissions could still slow down the inevitable accumulation of impacts and help us to adapt, the authors write in their paper.

作者在他们的论文中写道:“我们认为，几个冰冻圈临界点已经危险地接近，但减少温室气体排放仍然可以减缓不可避免的影响积累，并帮助我们适应。”

The nine active tipping points identified by the team include warming ice regions in the Arctic, Antarctica, and Greenland, in addition to dramatic changes underway in boreal forests, Atlantic Ocean currents, the Amazon rainforest, warm-water coral systems, and thawing permafrost.

该小组确定的9个活跃的临界点包括北极、南极洲和格陵兰岛的变暖冰区，此外，北方森林、大西洋洋流、亚马逊雨林、暖水珊瑚系统和融化的永久冻土层也正在发生巨大变化。

While some of these destabilised systems may appear to be unrelated to one another, the researchers warn increasing evidence suggests the disparate crises are actually linked together – and in fact are part of a global continuum of climate destabilisation that amplifies itself in numerous alarming scenarios.

虽然这些破坏稳定的系统可能看起来彼此无关，但研究人员警告称，越来越多的证据表明，这些不同的危机实际上是联系在一起的——事实上，它们是全球气候不稳定连续体的一部分，在许多令人担忧的场景中，这种不稳定会自己放大。

As soon as one or two climate dominoes are knocked over, they push Earth towards others, says Earth systems scientist Will Steffen from the Australian National University.

澳大利亚国立大学的地球系统科学家威尔·史蒂芬说:“一旦一两块气候多米诺骨牌被推倒，它们就会把地球推向其他地方。”

The findings are reported in Nature.

研究结果发表在《自然》杂志上。