Cumulus is composed ofWater dropComposition, but sometimes accompanied byIce crystal, which is mainly caused by air convection rising and coolingsteamhappencoagulationAnd formed.Therefore, the shape characteristics of cumulus are closely related to the characteristics of air convection.
Cumulus clouds are usually found in humid areas andTropical regionIt occurs, but sometimes in dry areas.Unless cumulus clouds become cumulonimbus clouds, there will be no showers, especially clouds and cumulonimbus clouds formed after noon indicate that showers are likely to occur.
Chinese name
Cumulus
Foreign name
Cumulus
Alias
Cu
Classification
Light cumulus, thick cumulus, broken cumulus
Genesis
Cumulus clouds are formed by rising gas blocks and condensation of water vapor
Cumulus（Grus japonensis : Cumulus, international abbreviation: Cu), divided intofair-weather cumulus、Cumulus cumulus、CatacumulusThe third type is a kind of cloud that develops vertically.Cumulus clouds are clearly defined, with convex top, flat cloud bottom, and most clouds are unconnectedDirect Cloud；It is caused by the convection of lower aircoagulationOr in winterSublimationAnd the cloud formed.The bottom of cumulus clouds is basically horizontal, and the top is circular arc. There are isolated, overlapping circular arch or linear arrangement, and the appearance is similar to cotton pile.
The height of the cumulus cloud bottom is generally 600-1200 meters in areas with high humidity and 3000 meters in dry areas. The cumulus cloud bottom is close to the ground in the morning and will rise in the afternoon.Cumulus clouds generally appear in the morning, most in the afternoon, and gradually dissipate in the evening.
features
Cumulus
The top of cumulus that develops vertically upwards is in a circular arc or arch shape, while the bottom is almost a horizontal cloud.The cloud body has clear boundaries.If the cumulus and the sun are in the opposite position, the middle of the cloud is brighter than the edge of the uplift;On the contrary, if it is on the same side, the middle of the cloud appears dark but the edge is bright golden;If the light shines on the cumulus from the side, the light and shade of the cloud are particularly obvious.[1]
origin
CumulusIt is formed by rising air blocks and condensing water vapor.[1]
When a mass of air rises, the horizontal distribution of its internal water vapor content and temperature is basically uniform at the beginning, thus generating water vaporcoagulationA cumulus cloud has a horizontal bottom.In the formation stage, the updraft is in the cloud and the updraft in the center of the cloud top is the strongest, the surrounding is weak, and the downdraft is outside the cloud, resulting in a round arched upward convex top of the cumulus and a clear outline.Cumulus clouds form mainly during the day, because sunlight heats the air. On the other hand, the ground also heats the air.Cumulus clouds can also form on the mountaintop during the day, because the hillside is heated faster than the valley bottom.This unstable heating forms convection in motion.Cumulus clouds are sometimes formed with or ahead of a cold front.Because in the front zone, the air is forced to rise.
Cumulus clouds are mainly formed in the daytime, because the ground will rapidly warm up under sunlight, making the air warm,Thermal convectionCausing cumulus formation.Cumulus clouds usually occur in humid and tropical areas, but sometimes in dry areas.Unless cumulus clouds becomeCumulonimbus cloudOtherwise, there will be no rainfall.
classification
Announce
edit
The shape characteristics of cumulus are closely related to the characteristics of air convection movement. The individual is obvious, the bottom is flat, the top is convex, and the clouds are not connected. The light receiving part of the cloud body is white and bright, and the cloud bottom is dark.Cumulus clouds can also be divided into three categories: thin cumulus, thick cumulus and detritus cumulus.[2]
fair-weather cumulus
fair-weather cumulus[2]
The cumulus formed when the air convection movement is not very strong (generally the vertical velocity is not more than 5m/s), the convection reach height is not much higher than the condensation height, the cloud upward development is weak, so the shape is flat, the top is slightly arched, and the horizontal width of the cloud is greater than the vertical thickness.Thick thin cumulus clouds have shadows in the middle.Pale cumulus clouds are isolated and scattered in the sky, and are common in sunny days.
Cumulus cumulus
Cumulus cumulus[2]
Cumulus formed when the air convection movement is strong (the vertical velocity can reach 15-20m/s).Since the height of convection is much higher than the height of doubt knot, the cloud body develops strongly upward. In the mature stage, the thick cumulus cloud can reach 4-5 kilometers, which is huge and towering. Its vertical thickness is greater than the horizontal width. Every strong updraft in the cloud makes the cloud top form a cloud bubble, so the cloud top of the cumulus cloud is a reselected dome shaped bulge, similar to cauliflower.Because the thick cumulus is thicker and larger than the light cumulus, it is not easy to penetrate the sun, so the concave and convex cloud surface has obvious shadows.The sunlit part is white and bright, while the shaded part is dark.Cumulus clouds can sometimes shower in middle and low latitudes.In the process of rapid development of cumulus clouds, if there is a relatively humid air layer above the cloud top, which is partially lifted up due to the influence of updraft, if there is moisture condensation, white cloud gauze like clouds can be formed, like a headband or hat covering the top of cumulus clouds. Such clouds are called cloud fu.Cumulus clouds generally do not produce precipitation, but sometimes it can also produce light rain.If there are thick cumulus clouds developing in the morning, it indicates that the atmospheric stratification is unstable. Cumulonimbus clouds often develop, and even thunderstorms occur.
Catacumulus
Catacumulus
Before the formation of thin cumulus or when the cumulus is blown away by the wind, it will form a broken edge, incomplete contour, and variable shape cumulus.Calculus clouds are mostly composed of 1-15 μ m water droplets.If it appears alone and has no obvious development, it generally indicates that the weather is stable.
