The atmosphere is the external part of earth surrounded by the layer of air. It consists of various gasses like Nitrogen, Oxygen, Carbon dioxide, inert gasses, water vapor, dust particles and much more.
On the basis of altitude from the earth surface and its pressure, atmosphere is divided into five different parts,
It is the thinnest layer of atmosphere, which extends from ground surface of the earth to 16 km.About 95% of the total volume of air is present in this layer. In this layer, the temperaturedecreases by 6.5 degree Celsius with each kilometer going up from sea level. All the metrological change like rainfall, snowfall, cloud formation, occur in this layer. This layer is most affected by human activities. The average temperature of this layer is 25 degree Celsius. The outermost region of this layer is called TROPOPAUSE.
It is the second layer of atmosphere which extends from 16-50 km from the ground level. Stratosphere is the protective layer of atmosphere as it contains ozone layer which prevents the entrance of UV rays from the sun towards earth. This layer is also called ozonosphere as the protective ozone layer is present in it. In this layer, the temperature will increase as we go up because of the presence of ozone gas. So, in this layer, no cloud is found and jet planes fly from the lower region of this layer. The outermost region of this layer is called STRATOPAUSE.
It is the third layer of the atmosphere which extends from 50 km up to 80 km up from the ground level. It is the coldest layer of the atmosphere where the temperature decreases from 2 degree Celsius to 110 degree Celsius. The meteors (shooting star) fall in this layer. In this layer, the wind blows with high speed in eastward direction in winter and westward direction in summer. The outermost region of this layer is called MESOPAUSE.
It is the fourth layer of the atmosphere which extends from 80km up to 720km up from the ground level. The lower part of this layer contains nitrogen and oxygen gas but in its upper part contains hydrogen and helium gas. While going up the temperature increase from 110 degree Celsius to 1200 degree Celsius. Due to high temperature, the air is present in ionic form so this layer is also called ionosphere. This layer is important for radio broadcasting and telecommunication as their wave travel from one part to another part of the world by bounding in the ions of gasses.
It is the outermost layer of atmosphere which extends to above 720 km from the ground surface. In this layer, very few hydrogen and helium gasses are present and due to less gravity sometimes they may escape into space. In this layer, temperature rises up to 6000 degree Celsius and this layer is also called fringe zone of atmosphere.
The two effects of the increasing quantity of greenhouse gases in the atmosphere with reasons are:
i. The temperature of the earth’s surface increases.
ii. It brings about change in weather.
i. The heat energy of the earth cannot be returned due to increase of the capacity of greenhouse.
ii. Due to increase of temperature, the rate of evaporation of surface water of ocean increases and the polar ice cap and glaciers start to melt and increase the sea level.
The canopy of air surrounding the earth is called the atmosphere. There are five main layers of the atmosphere. They are Troposphere, Stratosphere, Mesosphere, Thermosphere and Exosphere.
The part of the troposphere nearest to earth's surface is very hot and as the height increases, the temperature gradually lowers down. The top most layer of troposphere, the tropopause, has the lowest temperature. About 6.5 degree Celsius temperature falls down per kilometer increase in height.
Troposphere contains heavy gases, water vapor, dust particles, smoke, etc.
Scientists forecast weather by studying the activities such as cloud, rain, frost, hail storm, fog, tornado, lightening, thunder, etc. that occur in the troposphere.
The stratosphere has abundant ozone which absorbs 99% of the ultraviolet rays coming from the sun. This absorbing of ultraviolet rays causes the temperature to be very high in the stratosphere.
In the lower region of thermosphere, molecules of nitrogen, oxygen, etc. decompose to form atoms. Its upper region comprises mainly helium and hydrogen. Since there is more effects of solar radiation in this region, the temperature is very high.
Strong wind blows in the mesosphere. The wind blows from west to east in winter and from east to west in spring.
The exosphere is called the fringe region of the atmosphere. This layer lies 720 km above the surface of the earth. The two advantages of this region are: i. In this layer, the amount of air is negligible. ii. Atoms and molecules moves very fast and is not affected even by the gravitational force of attraction.
The portion of the atmosphere at the top of the troposphere is known as the tropopause. The temperature in this part of the atmosphere is lower than the troposphere.
The average temperature of troposphere is ______.
20 Degree Celsius
25 Degree Celsius
24 Degree Celsius
15 Degree Celsius
The thinnest layer of the atmosphere is ______.
Stratosphere extends from _______.
50 km up to 90 km up from the ground level
40 km up to 80 km up from the ground level
50 km up to 80 km up from the ground level
50 km up to 100 km up from the ground level