我們經常會有這樣的感受：在溫度一樣的時候，有風的天氣比無風的要冷一些。這似乎是一個再平常不過的現象了，但是你知道真正的原因嗎？就讓下面這篇文章來為你解答吧。

Anyone who's been outside on a windy, winter day knows it's a lot more difficult to stay warm than on a calm day with the same temperature.

On a calm winter day, our bodies warm up a thin layer of air close to our skin -- called the boundary layer -- and that helps to insulate us from the cold air. However, when the wind starts to blow, it strips away this boundary layer and our skin is more exposed to the cold air.

Because wind chill speeds up the rate at which your body loses heat, it can be dangerous. Each year in Canada, more than 80 people die from overexposure to the cold.

（北京林業大學通訊員邢元媛供稿 英語點津 Annabel 編輯）