“Looking at the sky, I wonder why I’m not a cloud. Why can’t I fly?” – Sometimes, while looking at the sky, such or similar thoughts arise.
What is a cloud and what is its role in the atmosphere?
Starting from the 19th century, the most curious people rose to the heights in hot air balloons in order to get a better view of clouds. However, the first knowledge about the nature of clouds was obtained after conquering mountain peaks.
A cloud is a cluster of water droplets or ice crystals at a certain height in the troposphere, which can be observed with the naked eye.
Clouds are formed with the participation of dust, to the particles of which droplets of liquid adhere.
Role of clouds in the atmosphere:
- Source of precipitation;
- Retain heat near the Earth’s surface;
- Partially block solar radiation.
What are the clouds?
When evaporating from various bodies of water, water particles rise to the colder layers of the atmosphere, where a process of their transformation into droplets, crystals or pellets takes place, depending on the surrounding temperature.
Droplets form at a temperature range of -11 to -16 °C. The process of crystallization occurs at lower temperatures.
Thus, clouds can be categorized as:
- Droplet clouds – formed by the condensation of water vapor;
- Ice crystal clouds – formed by the freezing of water droplets into ice crystals;
- Mixed clouds – a combination of water droplets and ice crystals.
How much does a cloud weigh?
The approximate weight of a cumulus cloud with a volume of one cubic kilometer exceeds 500 tons. To better visualize the significance of this number, let’s convert it to the number of elephants. Almost one hundred creatures together weigh as much. The weight of a thundercloud reaches the weight of 200,000 elephants.
Do all clouds have the same weight?
The weight of all clouds is different. Accordingly, they are arranged in the air as if in layers based on their weight. The lightest ones occupy the upper layer of the troposphere, and the heavier the cloud, the closer it is located to the Earth’s surface.
Why don’t clouds fall to the ground?
A heavy cloud does not fall because it is made up of millions of droplets, each weighing more than two microns. To create a raindrop, a large number of cloud droplets need to be collected together. However, liquid droplets cannot remain in the low-lying layers of the troposphere for long, so they fall to the earth’s surface as rain.
Is precipitation important for clouds to exist?
The lifespan of a cloud depends directly on the atmospheric humidity. When the humidity is low, clouds begin to evaporate, sometimes only lasting for up to fifteen minutes in the endless blue skies. With higher humidity, the likelihood of precipitation increases, which extends the life of the cloud several times.
Do other planets have clouds?
Our planet is not the only one in the Solar System where clouds exist. Such air-droplet masses have been found on Venus, Mars, Saturn’s moon Titan, and Neptune’s moon Triton. However, their nature is significantly different, which is explained by the surrounding conditions. For example, the clouds of Jupiter and Saturn consist of layers of ammonia, ammonium hydrosulfide, and water.
Uranus and Neptune have clouds of methane gas.
Above the surface of Venus, the basis of such formations is sulfur dioxide. It has been scientifically proven that the heaviest clouds in the Solar System are spread over Venus.
