By Joseph , Jose , Mark:

Our project is about Cirrus.

1.Cirrus Cloud

Sometimes, these clouds are so extensive that they are virtually distiguishable. from one another, forming a

sheet of cirrus called cirrostratus . Sometimes convection at high altitudes produces another form of cirrus called

cirrocumulus, a pattern of small cloud tufts which include droplets of supercooled water. The tearm is also used for certain intterstellar clouds composed of sub-micrometre sized dust grains. Jet stream-powered cirrus clouds can

grow so large that they stretch across continents, and yet they are still only a few kilometers deep. They can

even form from the outflow of cyclones or the anvils of cumulonimbus clouds.

2.Various Sub forms Cirrus clouds come in six distinct sub

forms : Cirrus castellan us is the form of a cirrus cloud that has a large shape rising up from the main cloud body . Cirrus intortus is an extremely contorted shape .Cirrus fibratus looks thinly striped and is the most common cirrus sub form .Cirrus clouds that strech across the sky. Cirrus uncinus clouds are hooked and are the form that is usually called`` mare`s trails1``. Kelvin-Helmhohz waves are a form of cirrus clouds that has been twisted by winds.

Cirrus Clouds High-level clouds form above 20,000

feet (6,000) and since the temperatures are so cold at such high elevation ,these clouds are primarily composed of ice crystals. High-level clouds are typically thin and white in appearance, but can appear in magnificent array of colours when the sun is low on the horizon.

Where and why do they form

``Cirrus`` in Latin means curl and these clouds are named because they resemble Wisps of curly hair. Cirrus are located high above the earth, as many as six miles high in the sky . Cirrus clouds form when a front of warm dry air meets a body of cool dry air . These clouds form in winter and in summer and the weather they cause depends on the speed and strength of the weather fronts , although they are often a sign that it is going to rain.

• 1.Late Afternoon cirrus clouds. 2.Environment cirrus clouds.

These are called cirrus clouds .

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Variation cirrus clouds.

Sunset cirrus clouds

Theend

By José Joseph and mark: