From threatening thunderheads to thin wisps, clouds play a critical role for life on this planet, and there’s more to clouds than meets the eye. Take a look below for 10 fun and interesting facts about clouds.

1. Heating of the surface of the Earth causing air to rise which condenses droplets of water to form clouds is one of the ways in which cloud formation takes place. The heating process is typically done by the Sun, but volcanoes and wildfires can also lead to intense heating of the Earth’s surface which can lead to swift formation of clouds which are called pyrocumulus.

2. According to NASA, around 67% of the surface of Earth is covered in clouds at any given time.

3. Cirrus are clouds that are made up of ice instead of water droplets.

4. During the spring and summer months, shelf clouds are common in an afternoon thunderstorm. These clouds roll like a shelf across the horizon.

5. Noctilucent clouds appear dozens of miles above the surface of the Earth. They are thin and wispy clouds, and they display a beautiful blue hue.

6. The colour spectrum of light is the reason the sky is blue, and the clouds are white. The light from the Sun starts out as white. However, it becomes scattered by particles that are located in the sky. The atmospheric particles are able to scatter blue light more compared to other colours, which gives the sky the blue color. However, when light passes through clouds, it interacts with larger particles (water droplets), which scatters all colours equally. This gives clouds their white colour.

7. Diamond Dust is fog that forms into ice crystals (instead of water vapour) and is an extremely rare event.

8. Stratus clouds are found at altitudes of less than 6,000 feet.

9. Clouds are a good omen in Iran.

10. It is a belief in Buddhism and Hinduism that cumulus clouds are spiritual cousins of elephants.