Voice of the Sea Ice: Antarctica's heartbeat

This week, it's the second episode of Voice of the Sea Ice, the Our Changing World miniseries about Antarctic sea ice.   This vast expanse of ice that grows each winter – effectively doubling the size of Antarctica – then melts each summer is like the heartbeat of our oceans.  And it has a big impact on the planet's climate, via its whiteness, insulating properties (or blanketness) and saltiness.  Dr Inga Smith, a sea ice physics expert from the University of Otago, takes Claire Concannon onto the ice at the front of Scott Base to explain.