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Snow Science© Debbie St. Germain
Earth is always moving and rotating around the sun. For many of us, this
time of year means the sun is further away. The days are becoming
shorter and colder. Although December 21st is the first day of winter,
cold and snow arrive earlier for many of us. Winter weather
brings us those white fluffy flakes we call snow.
All of this is happening in the part of our atmosphere called the troposphere. This is the lowest layer of our atmosphere, the layer that contains the water which makes clouds. In the clouds there are ice crystals in the upper portion and water droplets below. The ice crystals attract the water droplets which freeze onto the ice crystals. As they stick together, they become too heavy to hang in the air. If the air below is cold enough they fall to the earth as snow. Millions of tiny droplets must join together to be heavy enough to fall to the ground. Snowflakes are so delicate they often bump and collide as they fall. By the time a snowflake reaches the ground it is a jumble of several snowflakes. The tiny ice crystals that join together make the delicate 6-sided hexagonal shapes. Johannes Kepler was the first scientist to discover that all snowflakes were six-sided. The first person to ever capture the pattern of snowflakes on film is Wilson A. Bentley. He placed snowflakes onto a microscopic slide and photographed them through the microscope's eye piece, A Photomicrograph. Snowstorms can be anything from a simple flurry to a blizzard. When snow is driven by winds of at least 35 miles per hour, reduces visibility by 1/4 of a mile and lasts for at least 3 hours, it is called a blizzard. Blizzards can produce heavy amounts of snow and the fierce winds blow the snow into high piles called snowdrifts. Sometimes you may have experienced a brief but intense snow storm. It seems to be a blizzard and reduces visibility but this should not be confused with a blizzard. Blizzards last at least 3 hours, brief storms such as these are called snow squalls. In the mountains where heavier amounts of snow cover the slopes with
The copyright of the article Snow Science in Science for Kids is owned by Debbie St. Germain. Permission to republish Snow Science in print or online must be granted by the author in writing.
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