官方APP下载:英语全能特训(微信小程序版,支持苹果手机、安卓手机)
创办于2003年
UNSV记不住?那就记中文谐音“忧安思危”吧!
  Slow and Steady Wins the Race!
UNSV英语学习频道 - Slow and steady wins the race!
公众微信服务号
英语全能特训(微信公众服务号)
UNSV英语学习频道淘宝网店
客服短信:18913948480
客服邮箱:web@unsv.com
初级VIP会员
全站英语学习资料下载。
¥98元/12个月

SCIENCE REPORT - Snow Facts

阅读次数:


VIP会员专享下载:(非VIP会员无权下载!如果想下载,但还不是VIP会员,请点此订购
下载方式:使用鼠标右键(注意是鼠标右键!)点击下面的MP3音频/MP4视频链接,然后选择“另存为…”。
PDF节目文稿 PDF节目文稿  MP3节目录音 MP3节目录音 
文章正文
同步字幕

This is the VOA Special English SCIENCE REPORT.

Winter weather has arrived in northern areas of the world. In much of the United States, winter means the return of snow. Last month, during a severe storm, about two meters of snow fell on the city of Buffalo, New York.

Snow
storm in Buffalo
Snow storm in Buffalo

Snow is a subject of great interest to weather experts. Experts sometimes have difficulty estimating where, when or how much snow will fall.

Snow is a form of frozen water. It contains many groups of tiny ice particles, called snow crystals. These crystals grow from water particles in cold clouds. They usually grow around a piece of dust. 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.

Snow crystals grow in one of two designs -- platelike and columnar. Platelike crystals are flat. They form when the air temperature is about fifteen degrees below zero Celsius. Columnar snow crystals look like sticks of ice. They form when the temperature is about five degrees below zero Celsius.

The shape of a snow crystal may change from one form to another as the crystal passes through levels of air with different temperatures. When melting snow crystals or raindrops fall through very cold air, they freeze to form small particles of ice, called sleet.

When snow crystals stick together, they produce snowflakes. Snowflakes come in different sizes. As many as one-hundred crystals may join together to form a snowflake larger than two-and-one-half centimeters. Snow contains much less water than rain. About fifteen centimeters of wet snow has as much water as two-and-one-half centimeters of rain. About seventy-six centimeters of dry snow equals the water in two-and-one-half centimeters of rain.

Each year, the continental United States has an average of one-hundred snow storms. An average storm produces snow for two to five days. Almost every part of the country has received snowfall at one time or another. Even parts of southern Florida have reported a few snowflakes.

Snow creates many problems for people traveling. But it also is important. Much of the water we use comes from snow. Melting snow provides water for rivers, electric power centers and agricultural crops. In the western United States, mountain snow provides up to seventy-five percent of all surface water supplies.

This VOA Special English SCIENCE REPORT was written by George Grow.

网友的学习评论(0条):
版权所有©2003-2019 南京通享科技有限公司,保留所有权利。未经书面许可,严禁转载本站内容,违者追究法律责任。 互联网经营ICP证:苏B2-20120186
网站备案:苏ICP备05000269号-1中国工业和信息化部网站备案查询
广播台