身为宇航员的塞勒斯具有观察地球的独特视角。他曾从太空中看到北极冰冠不断消失的景象。在陆地上，他则借助电脑模式和地球观测卫星对复杂的气候数据进行提炼分析。

现在，北极地区正在以地球其他地方两倍的速度变暖。

人们不需到太空便可以看到这些影响。你和距你最近的沿海地区都可能面临以下危险：

• 海平面升高：人口占世界38%的沿海社区可能遭遇洪水灾，甚至可能被摧毁。
• 北极“镜”缩小： 冰雪折射的减少使地球上的更多热量无法散出，导致所有地方的温度更快升高。
• 极端天气：随着北极融化改变着北半球高空气流规律，干旱、高温和洪水可能更频繁出现。
• 鱼群转移： 北极海域急剧变化导致鱼群转移，使渔业受影响。
• 山火：更干燥的冬季导致更多的火灾。
  
• 永冻层不再永冻： 北极地下冰层正在解冻，有可能释放出数十亿吨温室气体。

你能做些什么?

哪怕只是在你的家乡为减少碳排放采取一些行动，都会有助于放慢北极冰雪消失的速度。如果你居住在沿海地区，你的社区可以采取措施，应对海平面升高造成的影响。



Here’s why you need to care about Arctic melting [video]

“If you rattle one part of the system, like the Arctic, you can be sure that you’re going to see impacts elsewhere,” says scientist Piers Sellers.

Sellers has a uniquely global perspective. As a NASA astronaut, he witnessed from space the continued melting of the Arctic icecap. On the ground, Sellers untangles complex climate data with computer modeling and Earth-observing satellites.

Right now, northern polar regions are heating up twice as fast as anywhere else on Earth.

You don’t have to be in space to see the effects. You and your closest coastline face these risks:

• Rising sea levels: Coastal communities, with 38 percent of the world’s population, could suffer flooding and possible destruction.
• Shrinking Arctic “mirror”: Without reflective snow and ice, more heat is trapped on Earth, accelerating warming everywhere.
• Extreme weather: Drought, heat and floods may increase as a melting Arctic shifts the northern polar jet stream.
• Fish flight: Arctic waters are changing so rapidly that fish populations are migrating, disrupting vital fisheries.
• Wildfires: Drier winters make blazes more prevalent.
• Permafrost not permanent: The Arctic’s layer of underground ice is melting, potentially releasing billions of tons of greenhouse gases.

What can you do?

Taking action to reduce carbon emissions, even in your hometown, can help slow the retreat of Arctic ice. And if you live on the coast, your community can take steps to respond to rising sea levels.