One of the most incredible features of life in the Arctic tundra is the spectacular display of ghostly, colourful lights that sometimes move across the sky.

 

This natural light show is called aurora borealis, or the northern lights.  It occurs when particles travelling towards the Earth from the Sun, called the ‘solar wind’, put pressure on the Earth’s atmosphere. If the build-up of pressure is large enough, it will create an electric voltage between the point
of pressure and the Earth’s magnetic poles. This electric charge can measure up to 10,000 volts. As solar wind particles move down the charge towards the poles, they crash into gas atoms
in the Earth’s atmosphere (such as oxygen) causing the gas atoms to give off light.

 

Auroras occur mostly near either of Earth’s two magnetic poles. They are called the southern lights
(or aurora australis) when they appear in the Antarctic skies.

 

Invented by the Inuit people of Canada and Greenland, the igloo is an amazing idea. Who would have thought you could use snow and ice to keep a family warm and safe through winter in the Arctic tundra?

 

This ingenious, instant home is made by using hand-carved blocks of snow as bricks. Each layer of blocks is carved so that it tilts towards the middle. As the circular wall gets higher, it joins in the centre as a dome.  

 

The cold is kept out by the thick snow blocks, which also trap heat. Icy drafts
are trapped by the tunnel entrance, which often has a bend in it. It’s also usually covered with a sealskin door.

 

To keep an eye on the outside world, a block of clear ice is sometimes used for a window. A slab of
snow covered with soft twigs and animal furs acts as a bed.