An Atmosphere is a layer of gases surrounding a planet or other material body, that is held in place by the gravity of that body. Many of the planets in this Solar System have atmospheres, but none that we know of have an atmosphere quite like ours – one that can support life.
The air is a mixture of several gases. The air encompasses the earth from all sides. The air surrounding the Earth is called the atmosphere. The atmosphere is an integral part of our Earth. It is connected with the earth due to the Gravitational Force of the earth. It helps in stopping the ultra violet rays harmful for the life and maintain the suitable temperature necessary for life. The air is essential for the survival of all forms of life on the earth.
The atmosphere is made up of different types of gases, water vapors and dust particles. The composition of the atmosphere is not static. It changes according to the time and place.
- Nitrogen N2 78%
- Oxygen O2 20.9%
- Argon Ar 9.34%
- Carbon dioxide CO2 3.84 %
- Neon
- Helium
- Methane
- Krypton
- Hydrogen
- Nitrous oxide
- Xenon
- Ozone
Water vapor is unique in that its concentration varies from 0-4% of the atmosphere depending on where you are and what time of the day it is. In the cold, dry artic regions water vapor usually accounts for less than 1% of the atmosphere, while in humid, tropical regions water vapor can account for almost 4% of the atmosphere. Water vapor content is very important in predicting weather.
Greenhouse gases whose percentages vary daily, seasonally, and annually have physical and chemical properties which make them interact with solar radiation and infrared Light (heat) given off from the earth to affect the energy balance of the globe.
The atmosphere also change composition with height and can be divided into two layers. The lower layer is called the homosphere and has the composition we talked about earlier. It’s top is approximately the Mesopause.
Above the homosphere lies the heterosphere, a layer in which the gases are stratified into four shells. The lowermost shell is dominated by molecular nitrogen (N2); next, a layer of atomic oxygen (O) is encountered, followed by a layer dominated by helium atoms (He), and finally, a layer consisting of hydrogen atoms (H).
Importance of various components of atmosphere are:-
(i) Oxygen is very important for the living beings.
(ii) Carbon dioxide is very useful for the Plants.
(iii) Dust particles present in the atmosphere create suitable conditions for the Precipitation.
(iv) The amount of water vapour in the atmosphere goes on changing and directly affects the plants and living beings.
(v) Ozone protects all kinds of life on the earth from the harmful ultra violet rays of the sun.
Structure and stratification of the atmosphere
Variations of temperature, pressure and density are much larger in vertical directions than in horizontal. This strong vertical variations result in the atmosphere being stratified in layers that have small horizontal variability compare to the variations in the vertical.
The atmosphere can be divided into five layers according to the diversity of temperature and density.
(a) Troposphere :-It is the lowest layer of the atmosphere. The height of this layer is about 18 kms on the equator and 8 kms on the poles. The main reason of higher height at the equator is due to presence of hot convection currents that push the gases upward.
This is the most important layer of the atmosphere because all kinds of weather changes take place only in this layer. Due to these changes development of living world take place on the earth. The air never remains static in this layer. Therefore this layer is called changing sphere or troposphere.
The environmental temperature decreases with increasing height of atmosphere. It decreases at the rate of 1 C at the height of 165 metre. This is called Normal lapse rate.
The upper limit of the troposphere is called Tropopause. This is a transitional zone. In this zone characteristics of both the troposphere and ionosphere are found.
(b) Stratosphere :-This layer lies above the troposphere and spread upto the height of 50 kms from the Earth’s surface. Its Average extent 40 kms.
The temperature remains almost the same in the lower part of this layer upto the height of 20 kms. After this the temperature increases slowly with the increase in the height. The temperature increases due to the presence of ozone gas in the upper part of this layer.
Weather related incidents do not take place in this layer. The air blows horizontally here. Therefore this layer is considered ideal for flying of aircrafts.
(c) Mesosphere :-It spreads above the stratosphere upto the height of 80 kms. from the surface of the earth. It’s extent is 30 kms. Temperature goes on decreasing and drops upto – 100 C.
(d) Ionosphere :-The ionosphere lies from about 80-400 km in height and is electrically charged as short wave solar radiation ionizes the gas Molecules. The electrical Structure of the Atmosphere is not uniform and is arranged into three layers, D, E, and F. Since the production of charged particles requires solar radiation, the thickness of each layer, particularly the D and E layers, changes from night to day. The layers weaken and disappear at night and reappear during the day. The F layer is present during both day and night. This change in height of the various electrically charged layers doesn’t effect the weather, but does effect radio signals.
The auroras also take place in the ionosphere since this is the electrically charged layer. The aurora borealis (northern lights) and aurora australis (southern lights) is closely correlated to solar flare activity.
(e) Exosphere:-This is the last layer of the atmosphere located above ionosphere and extends to beyond 400 km above the earth. Gases are very sparse in this sphere due to the lack of gravitational force. Therefore, the density of air is very less here.,
The atmosphere is the layer of gases that surrounds the Earth. It is held in place by the Earth’s gravity. The atmosphere is made up of many different gases, but the most common are nitrogen, oxygen, argon, and carbon dioxide.
Nitrogen makes up about 78% of the atmosphere. It is a colorless, odorless gas that is essential for life. Oxygen makes up about 21% of the atmosphere. It is a colorless, odorless gas that is necessary for breathing. Argon makes up about 0.9% of the atmosphere. It is a colorless, odorless gas that is inert, meaning it does not react with other substances. Carbon dioxide makes up about 0.04% of the atmosphere. It is a colorless, odorless gas that is a greenhouse gas, meaning it traps heat in the atmosphere.
The atmosphere also contains water vapor, which is the gaseous form of water. Water vapor is important for the Earth’s Climate because it helps to regulate the Earth’s temperature. The atmosphere also contains trace amounts of other gases, such as helium, neon, methane, and ozone.
The atmosphere is divided into five layers: the troposphere, stratosphere, mesosphere, Thermosphere, and exosphere. The troposphere is the lowest layer of the atmosphere. It is where most of the Earth’s weather occurs. The stratosphere is the next layer up. It is where the ozone layer is located. The ozone layer protects the Earth from harmful ultraviolet radiation from the sun. The mesosphere is the third layer up. It is the coldest layer of the atmosphere. The thermosphere is the fourth layer up. It is the hottest layer of the atmosphere. The exosphere is the outermost layer of the atmosphere. It is very thin and extends into space.
The atmosphere is stratified, meaning that the composition of the atmosphere changes with altitude. The lowest layer of the atmosphere, the troposphere, is where most of the Earth’s weather occurs. The troposphere is heated from below by the Earth’s surface. This heat causes the air in the troposphere to rise. As the air rises, it cools and condenses, forming clouds. The stratosphere is the next layer up. The stratosphere is heated from above by the ozone layer. The ozone layer absorbs harmful ultraviolet radiation from the sun. The mesosphere is the third layer up. The mesosphere is the coldest layer of the atmosphere. The thermosphere is the fourth layer up. The thermosphere is the hottest layer of the atmosphere. The exosphere is the outermost layer of the atmosphere. It is very thin and extends into space.
The atmosphere is essential for life on Earth. It provides us with oxygen to breathe, protects us from harmful radiation, and helps to regulate the Earth’s temperature.
What is the atmosphere?
The atmosphere is the layer of gases that surrounds the Earth. It is held in place by gravity and protects the Earth from harmful radiation from the sun.
What are the layers of the atmosphere?
The atmosphere is divided into five layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere.
What is the composition of the atmosphere?
The atmosphere is made up of about 78% nitrogen, 21% oxygen, and 1% other gases.
What is the temperature of the atmosphere?
The temperature of the atmosphere decreases with altitude. The troposphere is the warmest layer, and the thermosphere is the coldest layer.
What is the pressure of the atmosphere?
The pressure of the atmosphere decreases with altitude. The troposphere is the densest layer, and the exosphere is the least dense layer.
What is the wind?
The wind is the movement of air from one place to another. It is caused by differences in air pressure.
What is the weather?
The weather is the condition of the atmosphere at a particular time and place. It is caused by the interaction of the atmosphere with the sun, the Earth’s surface, and the Oceans.
What is climate?
Climate is the average weather conditions over a long period of time. It is determined by the latitude, altitude, and Landforms of a region.
What is Global Warming?
Global warming is the long-term heating of Earth’s climate system observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere. The term is frequently used interchangeably with the term Climate Change, though the latter refers to both human- and naturally produced warming and the effects it has on our planet. It is most commonly measured as the average increase in Earth’s global surface temperature.
What are the causes of global warming?
The main cause of global warming is the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide. These gases trap heat in the atmosphere, causing it to warm.
What are the effects of global warming?
The effects of global warming are already being felt around the world, and they are expected to become more severe in the future. These effects include rising sea levels, melting Glaciers, more extreme weather events, and changes in plant and animal life.
What can we do to stop global warming?
There are many things we can do to stop global warming, including reducing our reliance on fossil fuels, investing in RENEWABLE ENERGY sources, and improving Energy Efficiency. We can also make changes to our lifestyles, such as driving less, eating less meat, and recycling more.
What is the future of global warming?
The future of global warming depends on the actions we take to reduce greenhouse gas emissions. If we do not take action, global warming will continue to cause severe problems around the world. However, if we take action to reduce greenhouse gas emissions, we can limit the effects of global warming and create a more sustainable future for our planet.
The atmosphere is composed of:
(a) nitrogen, oxygen, argon, carbon dioxide, and other gases
(b) water vapor, dust, and other particles
(c) both (a) and (b)The atmosphere is divided into four layers:
(a) the troposphere, the stratosphere, the mesosphere, and the thermosphere
(b) the troposphere, the stratosphere, the mesosphere, and the exosphere
(c) the troposphere, the stratosphere, the mesosphere, and the ionosphereThe troposphere is the layer of the atmosphere closest to the Earth’s surface. It is where most of the Earth’s weather occurs.
(a) True
(b) FalseThe stratosphere is the layer of the atmosphere above the troposphere. It is where the ozone layer is located.
(a) True
(b) FalseThe mesosphere is the layer of the atmosphere above the stratosphere. It is the coldest layer of the atmosphere.
(a) True
(b) FalseThe thermosphere is the layer of the atmosphere above the mesosphere. It is the hottest layer of the atmosphere.
(a) True
(b) FalseThe ionosphere is a region of the atmosphere that is ionized by solar radiation. It is important for radio communications.
(a) True
(b) FalseThe atmosphere protects the Earth from harmful radiation from the sun.
(a) True
(b) FalseThe atmosphere helps to regulate the Earth’s temperature.
(a) True
(b) FalseThe atmosphere is essential for life on Earth.
(a) True
(b) False