NBC晚间新闻 严寒天气引起对气候变化的怀疑（在线收听）

Across the globe the weather picture is one of Fire and Ice. Bone-numbing record cold in the Midwest. Fire and record heat in Australia. 120 degrees and hotter this month. What that really means is that fires will be uncontrollable. They'll be fast moving. And yo-yo weather cycles. After the deep freeze in the U.S., a 50 degree rebound in some cities within days. Hard to believe when you're frozen like an icicle. But experts say that arctic blast is in fact further evidence of climate change. In response to president Trump's skepticism, the weather experts at NOAA tweeting winter storms don't prove that global warming isn't happening.

Here's why. At the North Pole scientists say the melting sea ice and ocean temperatures have caused the walls of the jet stream or polar vortex to break open like a dam in places. That has allowed arctic air to escape, rushing south into the Midwest. Not only is greenhouse gas warming impacting the planet but it's really beginning to kick in and it's kicking in in the parts of the planet that are most sensitive, in particular Arctic sea ice regions and the Arctic. All of us are feeling the effects. Still over the past decade the US has broken high temperature record twice as often as cold ones.

现在在全球范围内，寒冷与炎热的天气交织存在。美国中西部地区经历着创纪录的刺骨的寒冷天气。而澳大利亚则经历着创纪录的炎热天气。在那里，本月温度达到了120度以上。这种高温天气意味着火势会难以控制。大火会迅速蔓延。现在人们也经历着上下起伏的天气变化。在美国，严寒过后的几天内，有些城市的温度反弹幅度达50度。在严寒中冻成冰柱的你是无法想象会发生这种变化的。但是专家认为，实际上，极地寒流是进一步证明气候变化存在的证据。特朗普总统对气候变化持怀疑的态度，美国国家海洋和大气局的气象专家在推特上回应了总统，他们说暴风雪的存在并不能证明全球变暖现象没有发生。原因如下，科学家表示，在北极的某些地方，融化的海冰和海洋温度使急流或极地涡旋的壁面像水坝一样破裂。这导致了北极气团急速冲向中西部地区。全球变暖不仅影响着这个星球，而且它真的开始惩罚人类，全球变暖正影响着地球上最敏感的一些区域，尤其是北极海冰区域和北极地区。所有人都受到了影响。尽管如此，在美国，过去十年，高温天气创纪录的次数是低温天气创纪录的次数的两倍。