Mirage: Why Does It Look Like There's Water On The Road?

The fake puddles of water that we see on the road on a sunny day is due to an optical phenomenon called a mirage, which is caused by the refraction (or bending) of light rays due to different temperatures of the air above the road. On a hot, sunny day, the sun heats the road a lot. However, because roads are generally black, they absorb a lot of heat and become hotter than light-colored objects. This increases the air temperature just above the surface of the road. Now, as the sun’s rays pass through relatively warmer air (and less dense air) just above the road, their speed increases slightly, and they change course, i.e., being refracted to reach the eyes of the observer. The water you see on the road is not really water but a reflection of the sky. Mirages are often observed on sunny days when the sweltering heat of the sun warms flat surfaces like roads and thus the air above these muggy asphalt tracks.