Main topic information 2
How are clouds formed?
Solar radiation heats the Earth’s surface. It also gradually warms the lower layers of the air. Warm air has less density than cold air, so it rises. Water vapour rises with it. In the higher, colder layers, the humidity increases, and the air becomes saturated with water vapour. Some of the water vapour liquefies and small water droplets form. They are so small that the rushing air carries them upwards. At low temperatures below zero and high humidity, ice crystals can form. We see large amounts of small water droplets or ice crystals in the sky as a cloud. The amount of clouds in the sky over a particular place is called cloud cover. It is one of the meteorological elements.
What types of clouds do we distinguish?
We can observe clouds of different shapes, composition and sizes in the sky. In meteorology, they are divided into different groups. They are called by Latin names and represented by symbols. According to their composition, they are divided into water, ice and mixed clouds, depending on their height – high, medium, low and vertical clouds, and according to their appearance, they are divided into three groups: stratiform, cumulus and wavy clouds.
Source: https://depositphotos.com/vector/different-types-clouds-names-sky-levels-illustration-488464470.html
Cirus
They form at very low temperatures – from minus 25°C to minus 40°C. Tall, white, and fluffy, they contain ice crystals and are very high in the atmosphere. They often form after a storm, produce no precipitation and are a harbinger of good weather.
Cirrostratus
Consists of ice crystals at a height of 6-12 km above the Earth’s surface. They spread out like a thin white veil and individual clouds cannot be distinguished. They can appear before a storm.
Altostratus/High-layered
These are like a grey pall and occur at mid-altitudes between 2-6 km and are 2-3 km thick. They contain ice crystals in the upper parts and water droplets in the lower parts. They may produce light rain or small snowflakes.
Stratus/Layers
Form a low cloud layer resembling fog at altitudes below 2 km. Occasional light rain. Often occurs at night in good weather. Consists exclusively of water droplets.
Nimbostratus/Layer-rain
These are low rain clouds up to 6 km thick and dark in colour. They contain supercooled water droplets and sometimes ice crystals. They cause heavy precipitation of rain or snow.
Cirrocumulus
High clouds with ice crystals at an altitude of 6-12 km. They have a fibrous appearance, with very small sizes in the form of curls, grains, and ripples. Some call them “lambs”. They herald windy but not rainy weather.
Altocumulus
Medium-altitude clouds located 2 to 6 km above the ground. Consists of water droplets. They have distinct edges and are wavy and white or grey. They are associated with a cold front when moist air rises over a cooler ground surface.
Stratocumulus
These are layered cumulus clouds at lower altitudes – below 2 km. They consist exclusively of water droplets and have large dark round domes. We can see them arranged in groups, waves or lines, sometimes the size of an entire continent. In this type of cloud, twilight rays are formed that gather towards the cloud below. They usually do not cause precipitation.
Cumulus
Cumulus clouds at low altitudes look like small fluffy white orbs. They are up to 20 km wide and 10 km high. The higher the cloud, the darker its colour. They usually herald good weather.
Cumulonimbus
Such clouds bring storms, hail, tornadoes, and snow. They are powerful, vertically located, the highest type of cumulonimbus clouds – up to 15 km above the Earth’s surface. Their upper part is flattened. They can produce violent thunder, heavy rain, hail and even tornadoes. They are a harbinger of storms.
