Cumulus clouds

The air-mass thunderstorm is the least severe of all thunderstorms. In its simplest form, an air-mass thunderstorm grows as a single cell when solar radiation heats the surface air in an unstable atmosphere. Its life cycle lasts around 30 minutes. Towering cumulus clouds are formed as in-cloud updrafts push moisture upward. The tower may reach a height about five times the diameter of the cloud base in the growth phase. 

Even though upward motion causes cooling of a parcel of air, the condensation of water vapor can maintain the temperature of a parcel of air above that of the surrounding air. When this happens, the parcel is buoyant and may accelerate further upwards. Indeed, this is an unstable situation which can result in violent updrafts at velocities of meters per second. Cumulus clouds are produced in this fashion, with other phenomena such as lightning, heavy precipitation and locally strong horizontal winds below the cloud (which provide the air needed to support the vertical motion). 

We see from this diagram that partial pressures of H2O at ordinary conditions range from very small values to perhaps 30 or 40 mbar. This corresponds to a mass concentration range up to about 25 g H20/m. In typical clouds, relatively little of this is in the condensed phase. Liquid water contents in the wettest of cumulus clouds are around a few grams per cubic meter ordinary mid-latitude stratus clouds have 0.3-1 g/m. ... 

In collections of naturally occurring particles, such as water droplets in a cumulus cloud, there usually will be a considerable dispersion of radii. This will be true even in laboratory experiments unless special care is taken. For such applications, (7.2) is expected to be a good approximation provided, of course, that the particles satisfy the conditions under which it was derived they must be large and weakly absorbing. For example, (7.2) has been incorporated in radiative transfer calculations for snow (Bohren and Barkstrom, 1974) and clouds (Twomey and Bohren, 1980). 

I have to search for it, says. I have to locate it, says. I have to detain it, says. I have to grab it, says. I have to call it, says. I have to whistle for it in the midst of terror, says. I have to whistle for it through the cumulus clouds. I have to whistle for it with the spirit of the day. 

It is now his everyday self, his wife and his family whom he speaks about. "Our children are going to grow up and live. I see. I see my wife, my little working woman. I love her. I speak to her through space. I speak to her through the cumulus clouds. I call to her spirit. Nothing will befall us." Man and woman, the couple and their children, that is his theme now that love for his family wells up in his heart. 

Clouds formed when the dew point is above the freezing point are Cumulus clouds and Stratus clouds. 

Cumulus clouds - having a flat base and rising domes... 

The optical thickness of the fog used in the above-described laboratory experiments is typical for clouds like cumulus or stratocumulus [76]. To extend those results to atmospheric scales, experiments have been performed with... 

ACTM models can make use of atmospheric parameters that are output from some parametrization schemes. Boundary layer parameters have to be calculated inside ACTM models or in pre-processing if they are not available from the meteorological model. Entrainment and detrainment rates in cumulus clouds could be provided if sufficiently sophisticated cumulus parametrization is used in the meteorological model. 

Arakawa A, Schubert W (1974) biteractions of cumulus cloud ensemble with the large-scale environment. Part I. J Atmos Sci 31 671-701... 

Cutrim, E., D. Martin, and R. Rabin. 1995. "Enhancement of cumulus clouds over deforested lands in Amazonia." Bulletin American Meteorological Society 76 1801-1805. 

The close connection between the forest and precipitations is clearly indicated by the preferential development of local cloud over the forested areas of Ama2on and, viewed from the air, great pillars of cumulus sometimes appear to arise from the very top of the forest. For example Friedman (1977) noted that the western half of Marajo Island, which is heavily forested, received daily rain throughout the year. While thunderstorms built up over the forested half, none appeared over the treeless savanna eastern half. 

Cloud types often are classified based on altitude. High clouds have their bases above 7 km (23,000 ft) and include the wispy mare s tail clouds known as cirrus the cirrocumulus, known as mackerel sky and the layers of cirro-stratus. Middle clouds have altitudes between 2 and 7 km (6500 to 23,000 ft), and are either the rounded altocumulus or the layered altostratus. Low clouds have bases from near Earth s surface to about 2 km (6500 ft), and include stratocumulus, stratus, and nimbostratus. Nimbostratus clouds usually bring rain or snow. Clouds with vertical development extend from about 2 to 7 km or more, and include cumulonimbus (thunderhead clouds) and cumulus. 

At these high pressure weather conditions, the sea breeze cloudiness is a familiar picture only directly at the coast. It is typical, too, that these particular cumulus clouds dissolve quickly toward the open Baltic Sea due to the prevailing down-welling of the air over the water. Because of often only weak thermal lift above the narrow and wooded coastal and island areas, however, this cloudiness is usually only weakly pronounced or does not appear at all. Also for this reason, these particular coastal regions have a longer duration of sunshine and thus a higher irradiation than the coastal hinterland. Usually in the late afternoon, the sea breeze system and concomitantly the whole seabreeze cloudiness breaks down. If hereafter a warm offshore breeze sets in, the daily maximum temperatures at the Baltic Sea coast occur only in the evening. 

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