The Earth’s atmosphere is composed of the
following molecules: nitrogen (78%), oxygen
(21%), argon (1%), and then trace amounts of
carbon dioxide, neon, helium, methane, krypton,
hydrogen, nitrous oxide, xenon, ozone, iodine,
carbon monoxide, and ammonia.
1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
5. Exosphere
6. Ionosphere
The troposphere is the lowest layer of our atmosphere.
We humans live in the troposphere, and nearly all
weather occurs in this lowest layer. Most clouds appear
here, mainly because 99% of the water vapor in the
atmosphere is found in the troposphere.
The stratosphere contains the ozone layer. Ozone
molecules in this layer absorb high-energy ultraviolet (UV)
light from the Sun, converting the UV energy into heat.
Unlike the troposphere, the stratosphere actually gets
warmer the higher you go.
Mesosphere extends upward to a height of about 85 km
(53 miles) above our planet. The temperatures once again
grow colder as you rise up through the mesosphere. The
coldest temperatures in Earth's atmosphere are found
near the top of this layer. The air in the mesosphere is far
too thin to breathe.
Thermosphere absorbs high-energy X-rays and UV
radiation from the Sun, raising its temperature to
hundreds or at times thousands of degrees. However, the
air in this layer is so thin that it would feel freezing cold to
us. In many ways, the thermosphere is more like outer
space than a part of the atmosphere. Many satellites
actually orbit Earth within the thermosphere.
Although some experts consider the thermosphere to be
the uppermost layer of our atmosphere, others consider
the exosphere to be the actual "final frontier" of Earth's
gaseous envelope. As you might imagine, the "air" in the
exosphere is very, very, very thin, making this layer even
more space-like than the thermosphere. In fact, air in the
exosphere is constantly - though very gradually "leaking" out of Earth's atmosphere into outer space.
The ionosphere is not a distinct layer like the others
mentioned above. Instead, the ionosphere is a series of
regions in parts of the mesosphere and thermosphere
where high-energy radiation from the Sun has knocked
electrons loose from their parent atoms and molecules.
The electrically charged atoms and molecules that are
formed in this way are called ions, giving the ionosphere
its name and endowing this region with some special
properties.
Weather is the behavior of the atmosphere—wind,
temperature, humidity, air pressure,
precipitation—at any given point on a planet's
surface at a given time.
Climate is the statistics of weather over long periods of
time. It is measured by assessing the patterns of variation
in temperature, humidity, atmospheric pressure, wind,
precipitation, atmospheric particle count and other
meteorological variables in a given region over long
periods of time.
The seasons are caused by the amount of light that the
surface of each hemisphere of Earth
receives during different parts the year. Because of the tilt
of the Earth's axis and its rotation, certain months of the
year result in more direct sunlight, but not necessarily
because they are closer to the sun.
A weather disturbance is a term used to describe a
change in atmospheric conditions or weather patterns.
According to the World Meteorological Organization, the
different weather disturbances are tropical cyclones,
intense tropical cyclones, low-pressure areas, very intense
tropical cyclones, tropical waves, tropical disturbances,
tropical depressions and zones of disturbed weather. It is
also referred to as natural disasters, as they are capable
of wreaking havoc on roads, power lines and buildings.
Air pollution is a mixture of solid particles and gases in
the air. Ozone, a gas, is a major part of air pollution in
cities. When ozone forms air pollution, it's also called
smog. Some air pollutants are poisonous.
1. Burning of Fossil Fuels
2. Agricultural activities
3. Exhaust from factories and industries
4. Mining operations
5. Indoor air pollution
1. Respiratory and heart problems
2. Global warming
3. Acid Rain
4. Eutrophication
5. Effect on Wildlife
6. Depletion of Ozone layer
1. Use public mode of transportation
2. Conserve energy
3. Understand the concept of Reduce, Reuse and Recycle
4. Emphasis on clean energy resources
5. Use energy efficient devices
A city system is a group of cities, which, in their
evolution, have become interdependent because of the
many relationship networks that they have and that
interconnect them to a greater extent than
other cities located in the environment.
1. Composting and Vermicomposting
2. Landfilling
3. Incineration
Composting is useful for the disposal of biodegradable
waste. The part of the garbage which can rot in nature to
form harmless substances is called biodegradable (plants
and animal waste). Different biodegradable waste can be
dumped in a pit. Here, it can be allowed to decompose
after which the garbage will convert into useful manure.
This is known as composting.
Vermicomposting is the use of red worms to make the
process of composting fast.
Advantages
• The useful component of the garbage can be converted into manures
which can enrich the soil.
• Degradable waste is easily disposed off.
A low-lying open area out of the city where garbage is
collected and dumped is known as a landfill. The garbage
is loaded into the truck and dumped in the landfill. When
that area is fully covered with the garbage, it is covered
with layers of soil. Now it can be converted into a park or
a playground.
Advantage
• It is an easy method of waste disposal.
Disadvantage
• Garbage remains open for a long period of time. This can attract flies and
cause various diseases.
Incineration is mainly used to dispose of the medical
waste. In this method, garbage is burnt at a high
temperature in a special furnace called Incinerator. This
reduces large amounts of garbage into a small amount of
ash which can be disposed of in the landfill site.
Advantage
• It is the most suitable waste disposal method to dispose of the medical and
contaminated waste.
Disadvantages
• Energy is used for burning which makes the method costly.
• It may lead to air pollution.
1.Reduce
2.Reuse
3.Recycle