Why are storm clouds dark, and how does the Earth produce a magnetic field?

We explore the curious questions that science can answer

Rain stopped play? Larger water droplets absorb and scatter more light (Getty)

Why do storm clouds tend to look darker than normal clouds?

Storm clouds have a lot of water in them in droplets that are larger than those in normal clouds. These larger droplets absorb and scatter more light than smaller ones, so the storm clouds look darker.

Is the ice crust on the polar seas made of falling snow? Also: at what temperature does the sea freeze? And are icebergs made of fresh water or of sea water?