VOA常速英语2014--地球变暖造成强风使南极保持凉爽

As Planet Warms, Intense Winds Keep Antarctic Cool 地球变暖造成强风使南极保持凉爽

Intense winds help Antarctica keep its cool despite climate change, according to a new study.

Scientists overwhelmingly agree global warming exists and humans are largely responsible, but  Antarctica seems to have bucked 1 the trend, with portions of it cooling, while the rest of the planet heats up.  

The key to Antarctic weather is the wind, says Australian National University climate scientist Nerilie Abram, lead author of a the study.

澳大利亚国立大学气候学家，该研究的主要作者娜莉莉亚·亚伯兰表示南极气候的关键是风。

“They control how far north the rain bands go out of the Southern ocean.And they are also really important for temperature and in particular for the temperature of Antarctica and also the Antarctic peninsula, which is the bit of Antarctica that juts 2 out right into the path of those westerly winds.”

“这些风控制来自南大洋雨带向北行进的距离。而且对于温度至关重要，尤其是南极和南极半岛而言，这里的南极点正好位于西风的路径上。”

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That westerly wind belt circulates the continent. The study in Nature Climate Change finds that those winds are now stronger and their path tighter than at any time in the past 1,000 years. That change has been especially prominent since the 1940s.

西风带在这片大陆上常年循环。而自然气候变化研究发现风势更强劲而且其路径比过去1000年的任何时候更为密集。自二十世纪四十年代以来改变尤其突出。

Abram and her team reconstructed Antarctica's climate history from ice cores. They conclude the wind has kept a large part of the continent cold, unlike anywhere else on the planet.

亚伯兰和她的团队从冰芯重新构筑了南极洲的气候历史。她们的结论是风造成这片大陆一部分寒冷异常,不像地球上的其他地方。

“But we can explain that because as those westerly winds are getting stronger, they are actually tying the cold air over Antarctica, and it stops warm air masses from being able to get over the continent and help to warm Antarctica.So this example of something that seems like a climate change paradox 3, we can actually explain by these greenhouse gases that are strengthening the westerly winds and isolating 4 parts of Antarctica.”

“但我们可以解释,因为那些西风越来越强,实际上是聚集了在南极的冷空气而且阻止能够穿过这片大陆帮助温暖南极的热空气。所以就这个例子而言,似乎是气候变化的一种悖论,实际上我们可以解释通过这些温室气体南极洲的西风正在加强并且正在隔离这片大陆的部分地区。”

But they are not isolating the Antarctic Peninsula and parts of the Western Antarctic ice sheet that lie directly in their path.

但这些风并没有孤立在其路径中间的南极半岛和南极冰盖西部的部分地区。

“So as those winds have strengthened and pulled in tighter around Antarctica, they are actually bringing warmer air over those parts, particularly over the Antarctic Peninsula.And this is the part of the southern hemisphere that is warming faster than anywhere else on Earth at the moment."

“因此随着那些风在南极洲附近加强并且更为密集,实际上是将热空气远离这部分地区,尤其是在南极半岛。这就造成南半球的部分地区变暖的速度比地球其他任何地方都要快。”

Abram says those westerly winds have deviated 5 from their natural course, which would have driven cold fronts into the southern hemisphere. Instead the air is trapped over Antarctica and keeping rain from falling on Australia.

亚伯兰表示这些西风已经偏离了其自然进程,这将使得冷空气进入南半球。相反空气被困在南极洲阻碍澳大利亚的降雨形成。

“What has been happening over the recent decades is that those westerly winds have been shifting south and we are getting fewer of those cold fronts and storms coming up and giving that really important rain.And that is why Australia is experiencing these very severe droughts.”

“在近几十年来发生的是那些西风已经转南,我们正经历越来越少的冷空气及风暴,真正重要的是降雨稀缺。这就是为什么澳大利亚正经历现在非常严重的干旱”。

Abram adds the Southern ocean winds, which have intensified 6 because of the warmer atmosphere, could revert 7 to a more normal pattern if action were taken to reduce greenhouse gases.

亚伯兰补充道南大洋的风从而加强是因为温暖的气候所致, 如果采取行动减少温室气体排放可以恢复到到正常状态。