The strange,elongated shape of hailstones

摘要

A TEAM of storm chasers spent years tracking down terrible weather across the US to establish this simple fact: hailstones aren't round. They have more complex shapes than previously thought and this knowledge could help meteorologists understand their formation and better predict the dynamics of hailstorms on weather radar. "It's along the same lines as 'no two snowflakes are alike' -we can say the same thing about hailstones," says Matthew Kumjian at Pennsylvania State University. He and his colleagues carried out a hailstone survey over the course of six years. The team chased hailstorms across the Great Plains of the US, positioning themselves in the likely paths of storms and using weather radar data to rush to the scene of each hail fall before it melted.