Last year was the hottest on record, oceans boiled, glaciers melted at alarming rates, and it left scientists scrambling to understand exactly why.
They know the extraordinary heat was fuelled by a number of factors, predominantly planet-heating pollution from burning fossil fuels and the natural climate pattern El Niño. But those alone did not explain the unusually rapid temperature rise.
Now a new study published Thursday in the journal Science says it has identified the missing part of the puzzle: clouds.
