Science of a snowman

Building a snowman allows the whole family to enjoy a fresh fall of snow. For a long-lasting snowy sentinel, fresh, litter-free snow is used in temperatures at or slightly below freezing. If the temperature is too high the snow will be too wet. If it is much colder, the snow will be too dry and powdery to form stable balls. A flat, sheltered site out of the wind is selected. Three tiered and firmly compacted balls of snow are created. Kept proportional in size, they are stacked in decreasing diameter from base to head. Pieces of coal are used to mark the snowman’s eyes, smile and buttons. A carrot creates a colourful nose, an old hat and scarf keep him snug, and arms made of sticks complete the effect. As well as providing a focal point in the snowy garden, a snowman also helps prevent flooding when temperatures rise by reducing the rate at which the snow used melts.