GROUP MEMBERS
• Hajira Amir.
• Dilawaiz Fareed.
• Qudsia Nadeem.
• Rida Suleman .
• Mahnoor Butt.
• Maimoona Ikhtiar.

GLOBAL
WARMING

Global Warming
•Definition:
A gradual increase in
the temperature of the
earth‘s atmosphere
generally attributed to
the greenhouse effect
caused by increased
levels of carbon dioxide,
CFCs, and other
pollutants.

History of Global
Warming
•When was the idea of global
warming first introduced?
•Svante Arrhenius (1859-1927)was
a Swedish scientist he was the fist
to claim in 1896 that fossile fuel
combustion may eventually result
in enhanced global warming.

Continue……
•Arrhenius predicted both carbon
dioxide level and temperature
increased from 1900-1999.
•Arrhenius published ‘Worlds in the
Making’, in which he describes ‘hot-
house theory’.
•Hot-house theory is basically Green
house effect.

Pakistan and Global Warming
•When was global warming first
noticed in Pakistan?
•Pakistan recorded one of the
highest temperatures in the
world – 53.5 °C (128.3 °F) – on
26 May 2010, the hottest
temperature ever recorded in
Pakistan.

Natural causes
 There are several events in the natural
world that can contribute to global warming.
 These natural events have been taking place for millions
of years, way before mankind’s existence, and will
continue to do so until the end of time. Some of them
are:

Forest Fire
• Forest fires emit carbon-
filled smoke into the
atmosphere.
• New forests’ growth is slow
and not stable enough to
produce the much needed
oxygen.

Permafrost
•A thick subsurface layer of soil
that remains below freezing
point throughout the year,
occurring chiefly in polar
regions.
•When frozen soil increases, it
keeps in the carbon and
methane gases.
•As permafrost thaws , Carbon is
released to the atmosphere in
the form of methane. As

Solar activity ~
Sunspots
•A spot or patch that appears from
time to time on the sun's surface,
appearing dark by contrast with its
surroundings. These are magnetic
storms on the surface of the Sun.
• Sunspots restrict the passing of
solar plasma, which in affect gives off
radiation.
•They change the energy radiating to
earth’s atmosphere, and thus
increase climate temperature.

Volcanic Eruption
•It occurs when hot materials are
thrown out of a volcano. Lava , dust
and gas are some of these ‘ejecta’.
•Terrible explosion that throw out
huge amounts of rock and ash and Kill
many people and destroys property .
•They spew millions of pounds of CO2
into the atmosphere at one time
when erupt .w
•Release other green house gases like
CH4, SO2, CO ,H2S and HCl.

Man made causes
 Processes in our daily lives are expelling chemicals and
foreign substances into the air that affect and increase
the natural greenhouse gases. This results in global
warming and changes the climate .
 Human activities contribute to climate change by causing
changes in Earth's atmosphere in the amounts of
greenhouse gases, aerosols (small particles), and
cloudiness.

Deforestation
•Deforestation is the cutting
down of trees and plants to
make way for any
development activity.
•The loss of our forests results
in release of much carbon
into the air, with not enough
oxygen to combat it.
• With more CO2 in the
atmosphere, more sun's
radiation are being reflected
back to earth.

Burning of Fossil
Fuels.
•Each time a fossil fuel burn, CO2
levels in the atmosphere increase.
•Coal is the major fuel that is burnt to
produce power. Coal produces
around 1.7 times carbon dioxide per
unit of energy.
•Auto mobiles, and other means of
transportation release CO2.
•Industries release various gases into
the water and air. CO2, CH4, and N2O
have different heat trapping
capability.

Mining activity
•Mining oil, coal and other
mineral products underlying in
deep beds allow methane, a
greenhouse gas, to escape from
the earth.
•Methane, like carbon dioxide
creates a thick shield over the
atmosphere trapping the sun’s
rays.
•Continued use of mining
operations will only increase
harmful gases .

Fertilizer Use
•Fertilizer is that it produces
nitrous oxide once it absorbs
the soil.
•Nitrous oxide is 300 times
more dangerous than carbon
dioxide.
•The EPA strongly warns that
the farming industry’s use of
fertilizer is one of the leading
causes of global warming.

Overpopulation
• Since CO2 contributes to global
warming, the increase in population
makes the problem worse because we
breathe out more CO2 in the
atmosphere.
•More people means more carbon
dioxide in the atmosphere.

• Sun’s energy passes
through atmosphere.
• 26% is reflected or
scattered.
• 19% absorbed by clouds
,gases, and particles.
• 4% reflected to space by
sun.
• 51% reaches the surface

• The green house effect is the
effect of atmospheric gases.
• Carbon dioxide absorbing
energy from the sun and earth
and trapping.
• It near the earths surface
,warming the Earth to a
temperature range that is
hospitable for life.

Car parked in sunlight:
• Glass lets in light.
• Glass keeps heat
from escaping.
• Cause the car to heat
up.

Green house gases are those that can absorb and emit infrared
radiations.
The primary green house gases in the Earth’s atmosphere are
• Water vapor
• Carbon dioxide
• Methane
• Nitrous Oxide
• Ozone
• Chlorofluorocarbons

• Human activities are significantly increasing atmospheric
conditions of many GHG’s.
•The most significant GHG directly affected by anthropogenic
activity, is the product of the oxidation of carbon in organic
matter, either through combustion of carbon-based fuels or the
decay of biomass.
• Natural CO2 sources include volcanic eruptions, respiration of
organic matter in natural ecosystems, natural fires, and exchange
of dissolved CO2with the oceans.

• Methane is produced by anaerobic decay of
organic material in landfills, wetlands, and rice
fields; enteric fermentation in the digestive tracts of
ruminant animals such as cattle, goats, and sheep;
manure management;
• Wastewater treatment; fossil fuel combustion; and
leaks from natural gas transportation and
distribution systems and abandoned coal mines.

• Nitrous oxide (N2O) is produced by fertilizer use,
animal waste management, fossil fuel combustion,
and industrial activities.
• Hydrofluorocarbons and perfluorocarbons are synthetic
chemicals that are used in a variety of industrial
production processes such as semiconductor
manufacturing.
• HFCs and PFCs are replacing CFCs in applications such as
refrigeration and foam-blowing for insulation.

Impacts of Global
Warming:
On humans:
• Climate change induced mortality
• Certain types of weather events are
affected.
• Climate change affect human health
• A changing climate affects population health
clean air and water, sufficient food, infectious
disease agents and
security of shelter
• A warmer and more variable climate leads
to higher levels of
some air pollutant.

On Animals:
• Penguins are at risk
• Glaciers are receding at an alarming
rate and
changing the environment of the
mountains
• Polar ice is melting
• Rise in water temperatures
• Mammals come out of hibernation
sooner
• Polar bears disappearing
• Plants moved to cooler areas

On plants:
• Due to rising temperatures, plants and trees
are not growing properly.
• The effect of global warming in plants is
caused by land and water temperatures as a
result surface and underwater plant life is
harmed.
• The plants of the mountain and Polar
Regions are especially at harm.
• Decrease amount of rain can cause
droughts.
• It could affect crop growth and quality,
livestock health, and pests.
• The sudden changes in temperature rise in
majority of the seasons affects the amount
of rainfall. This can seriously damage the
growing of crop.
.

On Oceans:
• Increased level of CO2 have led
to ocean acidification.
• Changes in Cryosphere.
• Drowning wetlands.
• Fish migration.
• Coral bleaching.

On buildings:
• A higher solar intensity resulting in
higher exterior and interstitial surface
temperatures and for the exposed
components, higher levels of UV and
resultant damage.
• Increased frequency and intensity of
wind and flooding event
• A milder climate will reduce the
durability of building materials and
affect the indoor climate of buildings

Solution to global warming
•For millions of years, the earth’s climate has
naturally fluctuated, changing up from warmer
periods to ice ages.
• However, within the past century, the earth’s
temperature has increased unusually fast; 1.2
to 1.5 degrees Fahrenheit to be exact.
•According to research studies, human
activities are hugely contributing to this
unusual spike in temperatures.

Reduce Emissions
• We must significantly
reduce the amount of heat-
trapping emissions we are
putting into the
atmosphere.
• As individuals, we can help
by taking action to reduce
our personal carbon
emissions
• Expand the use
of renewable energy and
transform our energy
system to one that is
cleaner

Stop Deforestation
• Tropical deforestation
accounts for about 10
percent of the world’s
heat-trapping
emissions.
• Reducing tropical
deforestation can
significantly lower
global warming
emissions from fossil
fuels.

Buy recycled products
• Order or buy products
that require less
packaging to cut down
on the amount of waste
• If there is no recycling
plant in your area, make
a point to start one.

Less driving
• Minimal driving is tantamount
to less emission.
• Choosing healthy activities
such as walking and riding a
bicycle is a great way to cut
back on atmospheric
emissions.
• These acts serve to minimize
the number of cars on the
road, hence, reducing
the possibility of global
warming.

Keep devices and appliances
switched off
• When not using
devices and appliances
such as computers,
laptops, ovens,
television and so on,
make sure they are
switched off.
• This act reduces the
amount of energy
expenditure by more
than 40 percent.

Be an energy conservation
ambassador
• Teach your friends,
family, and neighbors
about recycling
and energy
conservation. Take
time to encourage
public officials to
initiate policies and
programs that
promote clean
environment.

Future predictions for global
warming
• Changing in
precipitation
• Rising sea level
• Acidic ocean water
• Impact on ocean
currents

Continue...
• More clouds
• Changes to life and the
carbon cycle
• Melting snow and ice
• Changing severe
weather