Warm Front - Development

Development

See also: Air mass

Air masses are large bodies of air with similar properties of temperature and humidity that form over source regions, and the warm air masses behind warm fronts are not only warmer but higher in humidity than the colder air preceding them. Because of a warm air mass’s higher temperature and thus lesser density, mixing between the two air masses is unlikely. Being lighter, the warm air mass is unable to displace the cooler air mass and instead is forced upward along the upper boundary of the colder air in a process known as overrunning. The boundary between the two air masses has a gradual slope of 130 and lifting is slow but persistent. As the air mass rises into regions of lower pressure, it expands and cools. As it cools, water vapor condenses and forms extensive cloud coverage. The first clouds to form along the sloping surface of the cold air are high cirrus, which thicken to cirrostratus and altostratus. Once the clouds have thickened to 2,500 metres (8,200 ft) from the earth’s surface, rain can begin to fall from the heavy nimbostratus cloud.

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Famous quotes containing the word development:

    “This was the Eastham famous of late years for its camp- meetings, held in a grove near by, to which thousands flock from all parts of the Bay. We conjectured that the reason for the perhaps unusual, if not unhealthful development of the religious sentiment here, was the fact that a large portion of the population are women whose husbands and sons are either abroad on the sea, or else drowned, and there is nobody but they and the ministers left behind.”
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    “The man, or the boy, in his development is psychologically deterred from incorporating serving characteristics by an easily observable fact: there are already people around who are clearly meant to serve and they are girls and women. To perform the activities these people are doing is to risk being, and being thought of, and thinking of oneself, as a woman. This has been made a terrifying prospect and has been made to constitute a major threat to masculine identity.”
    —Jean Baker Miller (20th century)

    “I could not undertake to form a nucleus of an institution for the development of infant minds, where none already existed. It would be too cruel.”
    —Henry David Thoreau (1817–1862)