Why does it actually get warmer when it snows? [ 2006-04-25 10:29 ]
Snowing does not
cause the warmth, the relative warmth causes the snow.
During very cold weather the capacity of the air to contain
moisture is greatly reduced. What water vapor remains
is deposited as frost. At the same time, evaporation is
reduced and therefore air humidity remains low. In these
conditions snow cannot form.
Warmer air can hold more moisture before saturation
point is reached and the water vapor begins to condense
out. So when warmer air moves into cooler areas, not only do
we feel the increase in temperature, but the excess vapor
precipitates as snow. |
moisture: 濕氣
saturation: 飽和
precipitate: 沉淀、突然下降
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