Snow blinds us with its gleaming white color because it
reflects beams of white light. Instead of absorbing light, snow's
complex structure prevents the light from shining through its
lattice formation.
A beam of white sunlight entering a snow bank is so quickly
scattered by a zillion ice crystals and air pockets that most of the
light comes bouncing right back out of the snow bank. What little
sunlight is absorbed by snow is absorbed equally over the wavelengths of visible
light thus giving snow its white appearance.
So while many natural objects get their blue, red, and yellow
colors from absorbing light, snow is stuck with its white color
because it reflects light.
Did you know?
- Snow can actually be seen in several different colors. Snow can
be red if the air during the snow formation contains red dust
particles. Snowflakes forming around these tainted dust particles
take on a reddish color. Red snow is found in those parts of Europe
where the air is filled with dust particles from the red sands of
the Sahara desert. In addition, certain types of algae stain snow
yellow, purple, orange, green, and red. In fact, some people believe
that the red algae that taints snow red actually looks and tastes
like watermelon!
- The word albedo is based on the
Latin word for white. Albedo refers to the amount/percentage of
light an object reflects. For instance, the albedo of water is low
while the albedo of snow if high.
- No two snowflakes have exactly the same shape.
- During a snowstorm, if the air temperature rises above 32
degrees Fahrenheit, the snow will melt and fall as rain.
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note:
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zillion: 庞大的数字 crystal: 晶体
wavelength: 波长 visible light: 可见光
albedo: 反射率 | |