十万个为什么·科学启蒙30篇（2）

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为什么我们在炎热的路面上看到海市蜃楼？

On hot days, air just above the road becomes much warmer and less dense than cooler air above.
Light travels faster in warm, thin air, causing it to bend upward slightly near the ground.
Your eyes and brain assume light moves in straight lines, so they misread the bent path.
This tricks you into seeing what looks like shimmering water or a mirrored sky.
The effect is strongest when there’s a big temperature difference between surface and air.
Mirages can also appear in deserts or over cold ocean surfaces, but with opposite bending.
Unlike reflections in mirrors, mirages form entirely from light refraction in layered air.
Cameras capture mirages the same way human eyes do—no special equipment needed.
Pilots sometimes see false horizons during landing due to similar atmospheric bending.
Understanding mirages helps meteorologists improve weather prediction models for heatwaves.