The 'Finger of Death' that Freezes Everything it Touches, Earth's Great Seasons, BBC Earth

Transcript

00:00In Antarctica, the freeze-up has come in spectacular style.

00:07In winter, the continent doubles in size.

00:13It's now bigger than the USA.

00:19The giant lock-up causes an urgent problem for one inhabitant.

00:25A Weddell seal.

00:28As the sea around her freezes, her breathing hole has begun to freeze over too.

00:34Without it, she'll suffocate.

00:37So she resorts to using her teeth to keep it open.

00:49But at least she has a retreat from the icy world above.

00:52The sea down here is a constant minus two degrees centigrade.

00:57That's over 50 degrees warmer than it is at the surface.

01:12And it's been like this for 25 million years.

01:22Beneath the layer of ice, this enchanted kingdom is protected from the extreme temperatures above.

01:32It's a wonderland of the strange and beautiful.

01:36In this safe, stable world, life explodes.

01:58But even here, winter cold can crash the party.

02:12As temperatures plummet on the surface, it triggers the growth of something sinister.

02:28This is a brinicle.

02:31Supercooled water sinking from above, forming a pillar of ice.

02:49For the creatures of the seabed, it's a stealthy finger of death.

02:57A river of ice imprisons everything in its path.

03:27Even those that think they've beaten the extremes of winter can get caught out.