Peat bogs are vital carbon sinks. Created when carbon-rich remains of plants are submerged in waterlogged land and turned into peat, they cover about 3% of the world's land, but they store twice as much carbon as all the world's forests combined. For our "Eye on Earth" series, Mark Phillips visited Scotland's Cairngorm mountains where efforts are underway to restore peat bogs in the name of climate emergency. Air Date: Nov 2, 2021