In nature, no two complex snowflakes are believed to ever be alike. However, in a laboratory two identical complex snowflakes have been created. There are many recreational activities that require snow, like snowboarding, skiing and snowmobiling. Search Search for: Search. Cold…white…fluffy…wet…frozen: all of these words describe snow. But what is snow and where does it come from. In colder climates, snow lies on the ground all winter. Spring snow melt is a major source of water supply to areas in temperate zones near mountains that catch and hold winter snow, especially those with a prolonged dry summer.
In such places, water equivalent is of great interest to water managers wishing to predict spring runoff and the water supply of cities downstream.
Measurements are made manually at marked locations known as snow courses , and remotely using special scales called snow pillows. When the snow does not all melt in the summer it evolves into firn, where individual granular elements become more spherical in nature, evolving into a glacier as the ice flows downhill.
Since fresh snow reflects 90 percent or more of short-wave radiation, and radiates energy nearly completely further into the infrared spectrum, little energy from the sun is converted into heat from the new snow, and much heat is lost. Many rivers originating in mountainous or high-latitude regions have a significant portion of their flow from snowmelt.
This often makes the river's flow highly seasonal resulting in periodic flooding. In contrast, if much of the melt is from glaciated or nearly glaciated areas, the melt continues through the warm season, mitigating that effect.
The world record for the highest seasonal total snowfall was measured in the United States at Mount Baker Ski Area , outside of the town Bellingham , Washington during the — season.
Mount Baker received cm 1, inches of snow, thus surpassing the previous record holder, Mount Rainier , Washington , which during the — season received cm 1, in.
Substantial snowfall can disrupt public infrastructure and services, slowing human activity even in regions that are accustomed to such weather. Air and ground transport may be greatly inhibited or shut down entirely. Populations living in snow-prone areas have developed various ways to travel across the snow, such as skis , snowshoes, and sleds pulled by horses, dogs, or other animals and later, snowmobiles.
Basic utilities such as electricity , telephone lines, and gas supply can also fail. In addition, snow can make roads much harder to travel and vehicles attempting to use them can easily become stuck. The combined effects can lead to a "snow day" on which gatherings such as school, work, or church are officially canceled. In areas that normally have very little or no snow, a snow day may occur when there is only light accumulation or even the threat of snowfall, since those areas are unprepared to handle any amount of snow.
In areas near mountains, people have harvested snow and stored it as layers of ice covered by straw or sawdust in icehouses. This allowed the ice to be used in summer for refrigeration or medical uses. Snowfall can be beneficial to agriculture by serving as a thermal insulator , conserving the heat of the Earth and protecting crops from subfreezing weather. Some agricultural areas depend on an accumulation of snow during winter that will melt gradually in spring, providing water for crop growth.
If it melts into water and refreezes upon sensitive crops, such as oranges, the resulting ice will protect the fruit from exposure to lower temperatures. Snow blindness also known as ultraviolet keratitis, photokeratitis or niphablepsia is a painful eye condition, caused by exposure of unprotected eyes to the ultraviolet UV rays in bright sunlight reflected from snow or ice.
This condition is a problem in polar regions and at high altitudes, as with every thousand feet approximately meters of elevation above sea level , the intensity of UV rays increases by four percent. Snow's large reflection of light makes night skies much brighter. However, when there is also cloud cover because snow is falling, light is then reflected back to the ground.
This greatly amplifies light emitted from city lights, causing the 'bright night' effect. Snow is not really white, it actually has no color. It looks like its white from reflections from the sun, no matter how little sun there is. Ultraviolet radiation — the sun sends different rays to Earth.
You will see some of them as sunlight. Earth Science. Please email or share this article!
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