Clouds represent the parts of the condensed steam weighed in the atmosphere which can be observed from the surface of the planet. These smallest crystals and droplets of water form quite bizzare shapes and very seldom stand still. Movement of clouds submits to certain regularities. Where do these eternal wanderers riveting on themselves attention of the person float?
Instruction
1. Formation of clouds depends on the speed of evaporation of water and particles of ice from the earth's surface. Rising together with flows of air up, drops of water and crystals are located at a certain height, concentrating also forming the figures, surprising in a form, differing in appearance, density and even color.
2. There is a set of types of the clouds having features and distinctive signs. The type of clouds and the nature of their movement indicate any given phenomena occurring in the atmosphere layer which is close to the surface of the planet. Watching movement of clouds, scientists make weather forecasts for several days ahead.
3. Clouds, of course, do not float on the sky in itself. They move after air flows, follow movement of air masses. The movement of clouds depends on features of distribution of atmospheric temperature, on the direction and wind force. Characteristics of air flows change depending on their remoteness from the surface of the planet, at the same time streams can amplify, weaken, change the direction.
4. A cloud – the concentrated steam which is much lighter than air. Temperature differences and pressure in the atmosphere lead to the movement of the huge mass of air entraining and clouds. It is established that movement of overcast is influenced by solar activity, greenhouse effect and even those changes of a temperature background which are caused by economic activity of the large cities.
5. So, clouds float there where at present the mass of air moves. Quite often in the sky it is possible to observe a paradoxical picture: clouds at the different levels move in opposite directions. Such phenomenon takes place when the warm air front approaches. And here at strong pressure decline the multidirectional movement of clouds can demonstrate approach of rainy weather with plentiful precipitation.