The variety of cloud forms observed in nature in various combinations is the result of complex processes developing in the atmosphere.
By the structure of clouds and associated precipitation, you can judge the state of the atmosphere not only at the time of observation, but also about its nearest changes. Clouds are one of the most important elements of weather. By the way, before the beginning of systematic aerological sounding, clouds were an important element of so-called indirect aerology, since clouds were used to judge processes in the lower half of the troposphere.
Despite the development of cloud physics research using flying laboratories and radio equipment, cloud observations are still being made visually. Therefore, determining the shape of clouds, their type and nature of development is one of the most difficult observations made at meteorological stations. Observations at the stations are conducted according to the international cloud classification system.
The modern classification is based on two characteristics: the appearance of clouds and the height of their location. This is the so-called morphological classification.
According to the international classification, clouds are divided by their appearance into 10 genera. Each of them has different types and varieties. Here are Russian and Latin names and their abbreviations:
1) Cirrus-cirrus (Ci);
2) cirrocumulus — cirrocumulus (Cc);
3) pinnate-layered-cirrostratus (Cs);
4) high-beam-altocumulus (Ac);
5) highly layered-altostratus (As);
6) layered-rain — nimbostratus (Ns);
7) layered-Cumulus — stratocumulus (Sc);
8) layered — stratus (St);
9) Cumulus — cumulus (si);
10) cumulonimbus— cumulonimbus (Cb).
These types of clouds between the earth's surface and the tropopause are divided into three tiers by their height.
The upper layer of clouds extends from 3 to 8 km in high latitudes, from 5 to 13 km in mid — latitudes, and from 6 to 18 km in low latitudes.
The average cloud layer is 2 to 4 km in high latitudes, 2 to 7 km in mid — latitudes, and 2 to 8 km in low latitudes.
The lower tier of clouds is bounded by the earth's surface and is 2 km high.
The upper layer clouds are Cirrus, cirrocumulus, cirrostratus, the cloud middle tier — altocumulus, to-lower layer clouds — stratocumulus, stratus, layered rain. Highly layered clouds usually occur in the middle tier, but often penetrate into the upper tier, and layered rain clouds from the lower one penetrate into the middle and even the upper tier. Cumulonimbus and cumulonimbus clouds, being the base in the lower tier, penetrate into the overlying tiers during development.
Layered and layered-Cumulus clouds are formed during slow ascent and adiabatic cooling of the air. Cumulonimbus and cumulonimbus clouds occur when air rises rapidly vertically and usually extend to the upper troposphere, so they are also called vertical development clouds.
The upper-tier clouds are made up of ice crystals. They are characterized by a fibrous and thread-like structure. Cirrus clouds sometimes occur as a result of the collapse of the upper part of cumulonimbus clouds, forming an "anvil".
Highly layered and layered rain clouds often form powerful layers, from which rain or snow falls depending on the air temperature.
Layered clouds of the lower tier are water-based or mixed. Their density is different. At low density, the sun shines through them. If layered clouds consist of ice crystals, then light circles (halos) are observed near the sun, which are formed as a result of refraction and reflection of light in ice crystals.
Layered-Cumulus and high-beam clouds are formed when rising air meets a layer with an inversion of temperature that prevents further air rise. These clouds usually have a small vertical capacity. When there is a large moisture content of air and convection in the cloud layer of air, layered Cumulus clouds can give small precipitation.
Cumulus and cumulonimbus clouds are formed due to thermal convection. Their vertical power depends on the power of an unstable stratified layer of air. If the moisture content of the air is low and the level of convection is low, i.e. at an altitude of 2-3 km there is a retaining layer of steadily stratified air, then flat Cumulus clouds arise — the so-called Cumulus clouds of good weather. They are typical for calm summer weather in anticyclones. On the contrary, with a large moisture content of the air and unstable stratification of it, extending to the middle and upper troposphere, a powerful Cumulus cloud develops and its transition to cumulonimbus. the precipitation Falling from these clouds has a stormy character and is often accompanied by thunderstorms, hail and squalls.
About the speed of vertical air movement. Layered, layered-rain and other frontal clouds are formed as a result of a slow and prolonged rise in air over a large area. These are so-called ordered vertical movements, whose speeds are measured in tenths or whole centimeters per second. In comparison with horizontal wind speeds, its vertical movements are many times smaller. However, these speeds are sufficient for such a significant adiabatic cooling to occur during the ascent of the air, which would cause condensation of water vapor and precipitation. At the same speeds, but downward movements of air, water vapor, on the contrary, is removed from the saturation state, clouds dissipate and clear weather occurs. This usually occurs in a system of amplifying anticyclones. It is not difficult to calculate, for example, that at the usual speed in these cases, equal to 3 cm/sec, the total air rise for 12 hours will be almost 1300 m, and for a day twice as much. Such rates of rising or falling air are characteristic of stable stratification of the atmosphere.
By the structure of clouds and associated precipitation, you can judge the state of the atmosphere not only at the time of observation, but also about its nearest changes. Clouds are one of the most important elements of weather. By the way, before the beginning of systematic aerological sounding, clouds were an important element of so-called indirect aerology, since clouds were used to judge processes in the lower half of the troposphere.
Despite the development of cloud physics research using flying laboratories and radio equipment, cloud observations are still being made visually. Therefore, determining the shape of clouds, their type and nature of development is one of the most difficult observations made at meteorological stations. Observations at the stations are conducted according to the international cloud classification system.
The modern classification is based on two characteristics: the appearance of clouds and the height of their location. This is the so-called morphological classification.
According to the international classification, clouds are divided by their appearance into 10 genera. Each of them has different types and varieties. Here are Russian and Latin names and their abbreviations:
1) Cirrus-cirrus (Ci);
2) cirrocumulus — cirrocumulus (Cc);
3) pinnate-layered-cirrostratus (Cs);
4) high-beam-altocumulus (Ac);
5) highly layered-altostratus (As);
6) layered-rain — nimbostratus (Ns);
7) layered-Cumulus — stratocumulus (Sc);
8) layered — stratus (St);
9) Cumulus — cumulus (si);
10) cumulonimbus— cumulonimbus (Cb).
These types of clouds between the earth's surface and the tropopause are divided into three tiers by their height.
The upper layer of clouds extends from 3 to 8 km in high latitudes, from 5 to 13 km in mid — latitudes, and from 6 to 18 km in low latitudes.
The average cloud layer is 2 to 4 km in high latitudes, 2 to 7 km in mid — latitudes, and 2 to 8 km in low latitudes.
The lower tier of clouds is bounded by the earth's surface and is 2 km high.
The upper layer clouds are Cirrus, cirrocumulus, cirrostratus, the cloud middle tier — altocumulus, to-lower layer clouds — stratocumulus, stratus, layered rain. Highly layered clouds usually occur in the middle tier, but often penetrate into the upper tier, and layered rain clouds from the lower one penetrate into the middle and even the upper tier. Cumulonimbus and cumulonimbus clouds, being the base in the lower tier, penetrate into the overlying tiers during development.
Layered and layered-Cumulus clouds are formed during slow ascent and adiabatic cooling of the air. Cumulonimbus and cumulonimbus clouds occur when air rises rapidly vertically and usually extend to the upper troposphere, so they are also called vertical development clouds.
The upper-tier clouds are made up of ice crystals. They are characterized by a fibrous and thread-like structure. Cirrus clouds sometimes occur as a result of the collapse of the upper part of cumulonimbus clouds, forming an "anvil".
Highly layered and layered rain clouds often form powerful layers, from which rain or snow falls depending on the air temperature.
Layered clouds of the lower tier are water-based or mixed. Their density is different. At low density, the sun shines through them. If layered clouds consist of ice crystals, then light circles (halos) are observed near the sun, which are formed as a result of refraction and reflection of light in ice crystals.
Layered-Cumulus and high-beam clouds are formed when rising air meets a layer with an inversion of temperature that prevents further air rise. These clouds usually have a small vertical capacity. When there is a large moisture content of air and convection in the cloud layer of air, layered Cumulus clouds can give small precipitation.
Cumulus and cumulonimbus clouds are formed due to thermal convection. Their vertical power depends on the power of an unstable stratified layer of air. If the moisture content of the air is low and the level of convection is low, i.e. at an altitude of 2-3 km there is a retaining layer of steadily stratified air, then flat Cumulus clouds arise — the so-called Cumulus clouds of good weather. They are typical for calm summer weather in anticyclones. On the contrary, with a large moisture content of the air and unstable stratification of it, extending to the middle and upper troposphere, a powerful Cumulus cloud develops and its transition to cumulonimbus. the precipitation Falling from these clouds has a stormy character and is often accompanied by thunderstorms, hail and squalls.
About the speed of vertical air movement. Layered, layered-rain and other frontal clouds are formed as a result of a slow and prolonged rise in air over a large area. These are so-called ordered vertical movements, whose speeds are measured in tenths or whole centimeters per second. In comparison with horizontal wind speeds, its vertical movements are many times smaller. However, these speeds are sufficient for such a significant adiabatic cooling to occur during the ascent of the air, which would cause condensation of water vapor and precipitation. At the same speeds, but downward movements of air, water vapor, on the contrary, is removed from the saturation state, clouds dissipate and clear weather occurs. This usually occurs in a system of amplifying anticyclones. It is not difficult to calculate, for example, that at the usual speed in these cases, equal to 3 cm/sec, the total air rise for 12 hours will be almost 1300 m, and for a day twice as much. Such rates of rising or falling air are characteristic of stable stratification of the atmosphere.
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