A new study published in the journal Nature shows that glacier ice walls are vital for the climate, as they prevent rising ocean temperatures and melting glacier ice.

An curved arrow pointing right. Engineers at Japan's Fukushima nuclear power plant have designed an "ice wall" to stop the spread of radiation into the groundwater. Produced by Maya Dangerfield.

Russians are marvelling at rare ice walls - in places 5m (16ft) high - towering on the shores of the Gulf of Finland near St Petersburg. They were created by storms lashing the region in recent days.