Subject : General Science Teacher: Mr Ehtisham Ul Haq Class: BS EDUCATION Semester: 2nd (Spring(2023-2027) Date Of Starting Of Semester : 4 September 2023 Date Of End Of Semester : 20 January 2024 University Of Sargodha Institute of Education These are the presentation slides that we prepare by our own research and work!

1. TOPIC NAME:
ENVIRONMENT
SUBMITTED TO:
SIR EHTISHAM UL HAQ
GROUP MEMBERS:
SALIHA TAYYAB (ROLL NO 08)
JAVERIA GHAUS (ROLL NO 21)
RIMSHA ARSHAD (ROLL NO 34)
KANWAL BATOOL (ROLL NO 28)
IRSA AMJAD (ROLL NO 20)
INSTITUTE OF EDUCATION
UNIVERSITY OF SARGODHA

2. Earth’s Environment
Composition of atmosphere
Different layer of atmosphere
Green house effect
Ozone layer
Reflection and absorption of energy
Climate changes
Types of pollution and their impact
Environmental pollution
Types of pollution
Effect of pollution

3. Earth’s Environment
Definition:
Earth’s atmosphere is a layer of gases that surrounds the planet
• It consist mainly of nitrogen about 78%and oxygen 21% with trace amount of
other gases like CO2, H2O vapours argon etc
Importance of atmosphere:
• Atmosphere plays a crucial role in supporting like on earth by
1. Regulating temperature
2. Providing oxygen for respiration
3. Protecting us from harmful solar radiation

4. Layers of Atmosphere:
• The earth’s atmosphere is divided in to several layers,each with distinct
characteristics
The Troposphere:
• The troposphere is the nearest layer to the earth.
• It is about 18km above earth’s surface .
• Most of the gas molecules and water vapour present in this layer.
• This is the layer where most of weather occurs.
The Stratosphere:
• This is above to the troposphere.
• It’s height is 50km from sea level.

5. The Mesosphere:
• Beyond the stratosphere,mesosphere is present.This is the coldest layer of
earth’s atmosphere.
• The temperature in this layer can be low as-100°C
• It is 85km above earth surface
The Thermosphere:
• It is the outermost layer of the atmosphere.
• It is the hottest layer where temp may be high as 200°C

6. Green house Effect
Defination
Greenhouse effect is the process by which radiations from the sun are
absorbed by the greenhouse gases and not reflected back into space. This
insulates the surface of the earth and prevents it from freezing

7. Gases responsible for greenhouse effect
• Carbon dioxide
• Methane
• Water
• Nitrous oxide5
• Ozone
• Chlorofluorocarbons (CFCs)

8. What is Greenhouse Effect ?
Carbon dioxide and water vapour absorb infrared radiations coming
to the earth and partly reflect it back to the earth’s surface. Due to
this, the surface of the earth gets heated up. This phenomenon is
called the greenhouse effect.

9. What is global warming?
The gradual increase in temperature due to the greenhouse effect
caused by pollutants, CFCs and carbon dioxide is called global warming.
This phenomenon has disturbed the climatic pattern of the earth.

10. Relationship between Green house effect and
Global warming
• The greenhouse effect is like a natural blanket around the Earth. It traps
some of the sun's heat, keeping our planet warm enough to support life.
However, when we add extra greenhouse gases like carbon dioxide from
burning fossil fuels, this "blanket" thickens, causing more heat to be
trapped. This extra warmth leads to global warming, which is the long-
term increase in Earth's average temperature, causing various
environmental changes and climate challenges.

11. 6.2 Ozone layer
The ozone layer is a protective layer of ozone gas high up in Earth's atmosphere
that absorbs the sun's harmful ultraviolet (UV) radiation, shielding us from its
harmful effects. It acts like a sunscreen for the planet.
What is ozone depletion?
Ozone depletion is when the ozone layer thins out or develops holes, allowing
more harmful UV radiation from the sun to reach the Earth's surface, which can
harm living organisms and ecosystems. It's like a protective shield getting weaker,
letting in more of the sun's harmful rays.

12. What is uv rays?
• UV rays, or ultraviolet rays, are a type of invisible light coming from the sun. They
can be harmful to our skin and eyes, like the sun's way of sending tiny invisible
sunburns.
What is cfcs?
• CFCs, or chlorofluorocarbons, are human-made chemicals that were commonly
used in products like air conditioners, refrigerators, and aerosol sprays. They were
phased out because they harm the ozone layer, allowing more harmful UV
radiation to reach Earth's surface.
What is ozone hole?
The ozone hole is a region in Earth's ozone layer where the concentration of ozone
gas is significantly lower than normal. This thinning or "hole" allows more harmful
UV radiation from the sun to reach our planet's surface.

13. Reflection and absorption of energy
Reflection:
• Reflection is the process by which waves, such as light, sound, or
electromagnetic waves, bounce back or change direction when they
encounter a boundary or surface. The incident wave's energy is redirected,
preserving its original properties like frequency, wavelength, and speed.
Explanation:
• When a wave encounters a reflective surface, like a mirror or a smooth water
surface, it bounces back according to the law of reflection, which states that
the angle of incidence is equal to the angle of reflection. This process allows
us to see objects in a mirror or hear an echo when sound waves reflect off a
wall.

14. Absorption:
• Absorption is the process by which energy from waves is taken in and
retained by a material, causing the material to heat up or exhibit other
changes. In this process, the energy of the incident wave is converted into
other forms, such as thermal energy or chemical reactions.
Explanation:
• When waves, like light or microwaves, interact with a material, some of their
energy is absorbed by the atoms or molecules in the material. This energy
can cause the material to warm up. For example, sunlight is absorbed by the
Earth's surface, leading to the heating of the ground. In the case of sound
waves, they can be absorbed by soft materials, reducing the
intensity of sound.

15. Climate changes
• Climate change refers to long term shift in global and regional weather patterns
and temperatures, primarily driven by human activities such driven by human
activities such burning of fossil fuels,deforestation and industrial processes.
Causes of climate changes:
• Burning of fossil fuels(like coal,oil,natural gas)
• Deforestation
• Industrial process which release green house gase like CO2,No2,CH4 trap heat
to sun and leading global warming.

16. Impact of climate change:
Climate change has far-reaching consequences including
• Rising sea level
• Intense stroms
• Heat waves
• Droughts
• Threats to ecosystem and biodiversity
Measurements for climate change:
• Adressing climate change is a global challenge that requires reducing GHGH
emission,transitioning to renewable energy resources andadopting sustainable
practices across sectors,like transportation,agriculture and industry.
• International efforts such as the Paris Agreement ,aim to unite countries in the
fight against climate change .

17. Types of pollution and their impact
What is pollution?
• The presence in or introduction into the environment of a substance which has
harmful or poisonous effects
Environmental pollution?
• Environmental pollution, the addition of any substance ( solid, liquid, or gas) or any
form of energy (such as heat, sound, or radioactivity) to the environment at a rate
faster than it can be diluted, decomposed, recycled, or stored in some harmless form.
What is air pollution and its cause
• Harmful contaminants (chemicals, toxic gases, particulates, biological molecules, etc.)
into the earth’s atmosphere. These contaminants are quite detrimental and in some
cases, pose serious health issues.
• Some causes that contribute to air pollution are:
• Burning fossil fuels
• Mining operations
• Exhaust gases from industries and factories

18. What is water pollution and its effect
• Water pollution is said to occur when toxic pollutants and particulate matter are
introduced into water bodies such as lakes, rivers and seas. These contaminants
are generally introduced by human activities like improper sewage treatment
and oil spills. However, even natural processes such as eutrophication can cause
water pollution.
• Other significant causes of water pollution include:
• Dumping solid wastes in water bodies
• Disposing untreated industrial sewage into water bodies
• Human and animal wastes Increases toxic chemicals
• Disruption of the ecosystemThreats to marine life

19. What is land pollution?
Land pollution refers to the degradation, contamination, or harmful alteration of
the Earth's surface and soil due to human activities. It occurs when pollutants,
such as chemicals, industrial waste, garbage, or toxins, are deposited or released
into the land, making it unhealthy or unsuitable for plants, animals, and humans.
• Land pollution can have effects on ecosystems agriculture human health
• The harmful pollutants responsible for polluting the environment are:
• Nitrogen oxide
• Sulphur oxide
• Mercury
• Particulate matter
• Chlorofluorocarbon
• Volatile organic compounds

20. Effects of rising pollution :
• Health Problems
• Dirty Air
• Water Pollution
• Trash Everywhere
• Climate Change
• Hurt Nature
• Expensive Cleanup
• Harming Wildlife
• Global Warming
• We should work to reduce pollution to keep our world clean and safe

21. Measures to reduce pollution:
• Use Public Transportation
• Switch to Clean Energy
• Energy Efficiency
• Reduce, Reuse, Recycle
• Green Transportation
• Proper Disposal
• Educations and Awareness
• Plant Trees
• Green Building Design