Fragmented forests have warmer canopies across much of the world

Breaking a forest into smaller patches creates more exposed edges.

A global study found that these broken-up forests often had warmer treetops, even when the amount of tree cover was similar.

The researchers think this may be linked to fragmented forests releasing less water vapor, which helps plants cool themselves.

Far northern forests were an exception: snowy gaps often reflected sunlight and were cooler.