Let It Snow! But in October
?
05 December 2011
Heavy snow in October in the northeastern United States brought down trees and caused damage to power lines
BOB DOUGHTY: This is SCIENCE IN THE NEWS, in VOA Special English. I’m Bob Doughty.
FAITH LAPIDUS: And I’m Faith Lapidus. Today, we will tell you everything you ever wanted to know about snow.
(MUSIC)
BOB DOUGHTY: Winter weather is returning to northern parts of the world. In the northern United States, winter can mean the return of snow. Some snow can begin falling in November. But large amounts of snow fell this past October, surprising many people. Almost three million people lost power and at least twelve people died when wet, heavy snow fell in New England. In some areas, the snow was two-thirds of a meter deep. Many trains and flights were delayed or cancelled.
Snow is a subject of great interest to weather experts. They sometimes have difficulty estimating where, when or how much snow will fall. One reason is that heavy amounts of snow fall in surprisingly small areas. Another reason is that a small change in temperature can mean the difference between snow and rain.
FAITH LAPIDUS: Just what is snow, anyway? Snow is a form of frozen water. It contains groups of ice particles called snow crystals. These crystals grow from water droplets in cold clouds. They usually grow around dust particles.
All snow crystals have six sides, but they grow in different shapes. The shape depends mainly on the temperature and water levels in the air.
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