A future without polar bears would be very sad, but the sea ice is not just essential for animals.
少了北极熊的未来将令人不胜唏嘘，可是海冰不仅是对于动物不可或缺。
It's a lifeline for many of the four million people who call the arctic their home.
更是以北极为家的四百万居民赖以为生的命脉。
Aleqatsiaq Peary lives in qaanaaq on Greenland's west coast, the most northerly inuit town in the world.
阿雷卡西亚克·佩瑞住在格陵兰西岸的卡纳克，全世界地处最北的因纽特城镇。
For centuries, life here has depended on the sea ice.
数百年来，这里的生活都要仰赖海冰。
Not only are dog sleds a way to reach neighbouring communities, which can be over 100 miles away,
狗橇不仅是前往距离可能超过一百英里邻近聚落的交通方式，
but, in a land where no crops can grow, travelling over the sea ice is a vital route to food, fur and livelihood.
而且在无法栽种农作物的土地上，在海冰上穿梭更是取得食物、毛皮与生计的要道。
But the dwindling of the sea ice is making this way of life not only difficult, but increasingly dangerous.
然而海冰的减少使得这种生活方式不仅变得艰难，更提高了危险性。
Today, they must turn back.
今天他们不得不回头。

For qaanaaq's 650 residents, the loss of sea ice is the loss of an entire way of life, and it is creating an uncertain future.
对于卡纳克的650位居民来说，失去海冰就等于彻底失去生活方式，衍生出一个不确定的未来。
And there's a reason for this accelerating speed of change.
而这种改变之所以加速不是没有原因。
In the last 30 years, over 14 trillion tonnes of ice have been lost from the arctic, creating a vicious cycle of ever-increasing temperatures.
过去三十年来，超过14万亿吨的冰从北极消失，造成持续增温的恶性循环。
Normally, large areas of snow and ice would act as a mirror, reflecting up to 85% of the sun's rays back into space.
通常，大面积的冰雪会有如一面镜子，将85%的阳光反射回到太空。
But as the ice melts, the great white mirror is being replaced by the darkness of the ice-free ocean.
可是由于冰块融化，庞大洁白的镜子被深色的无冰海面取代。
The dark ocean absorbs the sun's rays, so causing even more ice to melt, creating a feedback loop that contributes to further warming.
深色的海洋会吸收阳光，因此造成更多冰块融化，形成回馈循环，导致进一步暖化。
Because of this, the arctic is now warming more than twice as fast as the earth as a whole.
由于这个缘故，北极目前的暖化速度是地球整体的两倍快。