How to stop megafires: Let some of them burn

Wildfires in North America are getting bigger, more frequent and more destructive, according to official statistics from the US government.

Why? Scientists say a warming climate combined with a century of fire suppression by the people who settled the US West has produced the perfect conditions for so-called “megafires,” fuelled by thicker and drier forests.

Our North America correspondent James Cook reports from the Colorado Rockies.