ATMOSPHERE

ATMOSPHERE

Is the outermost layer of Earth's atmosphere,fase gas that surrounds the Earth's surface. There ranging from sea level, which is currently considered to be 0:00 m elevation, continue upwards. Upper boundary is not clear, so it can not be determined boundary between atmosphere and outer space with the firm. Based on observations of temperature, the atmosphere is divided into 4 parts or layers. The bottom layer, or layer closest to the earth's surface, where temperature decreases with increasing elevation is called the troposphere, which means the area where the air is turned. In this layer occurs clouds, precipitation, storms and so on. so that this layer is also called the weather layer, its thickness is uneven, the average to a height of 12 km.

Top layer is the stratosphere, and the displacement of this layer is called the tropopause. Stratospheric temperature constant, averaging -55  C to a height of 20 km, then ascending in elevation, up to a height of 50 km. The rise in temperature at this altitude because this area is the concentration of ozone. As we all know that ozone absorbs ultra violet rays emitted by the sun. This absorption causes the temperature increase in this layer. Later on it found Mesosfir layers, beginning with the transition zone called the stratopause. And Termosfir, after the mesopause. Above an altitude of 80 km to 320 km consists of charged particles (ions), hence the name ionosphere.

This layer is very important in communication, it reflects radio waves. The radio waves from one hemisphere can be accepted in other parts, because the signal reflected by the layer ionsfir.

And above the ionosphere, up to 800 km. Exosfir layer called, consisting of helium and hydrogen gas at the same ratio of 50%.

Atmospheric Composition

The air contained in the atmosphere, it seems only a single kind of material, but is actually composed of various materials consisting of gases and fine particles. Its composition is not fixed from time to time and every place. Gas near the Earth's surface there are as dry air (dry air) and the moist layer.

Dry air contains gases nitrogen, 78%, 21% oxygen, argon 0.9% and 0.03% carbon dioxide. Everything is almost 99.99%. While the rest, approximately 0.01% consist of the gases helium, neon, krypton and xenon, which are classified as inert gases and is the result of chemical reactions. Helium occurs as a side product in the radioactive process.

A moist layer of air containing some water vapor. Levels of water vapor in the atmosphere is not the same in all places, is highly dependent on temperature. At a temperature of 0 ° C.

not more than 5 grams H2O/m3 and at 40 ° C is not less than 55gr/m3.

In humid climates can reach 5% by volume, whereas in dry climates (the poles for example) only 0, 01% by volume. The amount of water in the atmosphere is 15.1015 kg, although it seems very small compared with the whole atmosphere, but this is very important as a source of water on earth.