A short film about an expedition to Tibet's Guliya Glacier, where scientists drilled a Stone Age ice core going back 600,000 years. Plus a report on what the ice core reveals.
Meltwater from the glaciers supplies water to 800 million people, so that loss would mean serious consequences for water management, food security, energy production.
The report shows the warming trend that's transforming the Arctic region is persisting. The Arctic shows no sign of returning to reliably frozen region of recent past decades, say scientists.