Atmosphere

Atmosphere to retain heat, resulting in our planet from the sun. It is like a blanket envelops the Earth's surface and protects humans, animals and plants from harmful ultraviolet cosmic rays. Without the air of the Earth would be lifeless as the moon. Scientists have found that the upper atmosphere is at an altitude of about 2000 kilometers. We live in a very dense layer, which is called - the troposphere. In the troposphere is about 80 percent of the atmosphere and almost all the water vapor. The thickness of this layer varies: at the equator, it reaches up to 18 kilometers over the poles 8 ... 10 kilometers. Here, in the troposphere, the formation of fog and clouds, rain and snowfall, storms and blizzards, storms and hurricanes. All these natural phenomena form the weather on our planet. Above the troposphere is the second layer, which is called - the stratosphere. Its thickness is about 50 ... 60 km. There is very little water vapor, so almost no clouds are formed. On the whole thickness of the stratosphere bitter cold minus 50 ... 60 degrees Celsius. Blow shrill, high winds, which never happens in the troposphere. Mesosphere - the next layer of the ocean air. Its height is about 55 ... 85 kilometers. In this layer greatly decreases the air temperature down to minus 70 ... 80 degrees Celsius. In the summer, in clear weather look in the sky. There, high above the ground you can see the shiny thin clouds, they are called silver. These clouds are formed at an altitude of 70 kilometers from the Earth's surface. In the middle of the atmosphere is fairly thick layer of warm air. Its temperature varies from 0 to +20 degrees Celsius. The reason that the realm of eternal cold invaded the heat is ozone. It is accumulated here. Ozone absorbs much of the destructive to living organisms ultraviolet rays. Above the mesosphere is located - the thermosphere. This is the widest layer of air of the Earth. His height was about 720 miles. In the thermosphere observed such interesting natural phenomena as the Northern Lights, flashes and other meteorites. If the Earth is not surrounded by the atmosphere, the sky above us has always been to densely black. On it day and night, the stars twinkle. There would be no rivers, no oceans or seas. In the sky there would be no single cloud. Read some of the phenomena occurring in our environment.