Meteorology or Weather Terms +
(topics about the study of the complex motions and interactions of the atmosphere, including the observation of phenomena; such as, temperature, density, winds, clouds, and precipitation)
Up until about 1800, there were no general classifications of clouds
Clouds were referred to poetically or as vague essences floating in the sky.
As an English manufacturing chemist and pharmacist, Luke Howard, like many who observed and studied the workings of the atmosphere at that time, was an amateur meteorologist.
Although he produced several landmark works including On the Modification of Clouds, The Climate of London, and Seven Lectures on Meteorology, the first textbook about weather, he was never trained as a scientist but from an early age, he had a fondness for nature and the weather, particularly the clouds.
Luke Howard divided clouds into basic shapes with Latin classifications: cumulus, stratus, cirrus, and nimbus.
Each cloud type is formed under different conditions.
His fascination with clouds started with the incredible skies of 1783 between May and August of that year. The Northern Hemisphere sky was filled with a "Great Fogg", a haze composed of dust and ash that caused brilliant sunrises and sunsets which resulted from the violent volcanic eruptions in Iceland (Eldeyjar) and Japan (Asama Yama).
In addition to the spectacle of the continuous volcanic ash in the sky, there was a fiery meteor which flashed across western European skies during the early evening of August 18, which was observed by the eleven year-old Luke Howard.
Before the beginning of the Nineteenth Century, most weather observers believed that clouds were too transient, too changeable, and too short-lived to be classified or even analyzed.
With few exceptions, no cloud types were named; they were just described by their color and form as each individual saw them: dark, white, gray, black, mare's tails, mackerel skies, wooly fleece, towers and castles, rocks and oxes-eyes.
Clouds were used in a few situations as weather forecasting proverbs, but mostly by their state of darkness or color:
"Red sky in morning, sailor take warning."
"Mackerel skies and mare's tails, make lofty ships carry low sails."
2. The weather conditions or patterns of specific areas of the world.
Although the earth's atmosphere extends 1,500 miles (2,414 kilometers) above the surface, the greatest bulk of the gases (about 75 percent) are within 10 miles (16 kilometers) of the earth's surface.
2. A powerful cold dry northeasterly wind that blows in the south of France.
3. A north wind that blows down the Rhone valley south of Valence, France, and into the Gulf of Lions.
It is strong, squally, cold, and dry which is the combined result of the basic circulation of a fall wind, and a jet-effect wind.
It blows from the north or northwest in the Rhône Delta, where it is strongest, from northwest in Provence and from northeast in the valley of the Durance below Sisteron.
A general mistral usually lasts for several days, sometimes with short lulls. It is most violent in winter and spring, and may do considerable damage.
The mistral has a variety of local names: mangofango in Provence; sécaire, maistrau, maistre, or magistral in Cévennes; dramundan in Perpignan; cierzo in Spain; cers in the Pyrenees, etc.
Composed of ice crystals, bright, silvery noctilucent clouds are visible at night because their height above the earth allows them to escape the planets' shadow.
- Temperature changes, weakening rocks by expansion and contraction.
- Frost, wedging rocks pushing them apart by the expansion of water when freezing.
- Unloading, the loosening of rock layers by the release of pressure after the erosion and removal of those layers.
It can fall as rain, snow, ice, frost, dew, and other forms of atmospheric water.
They form small balls of ice with space between them.
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