Natural Science 13
DLS – College of Saint Benilde
Hand-out 9: The Atmosphere
Lecturer: Mr. Jose Mari Balines Gonzales
M.Sc. in I.T. for Natural Resources Management
Objectives:



To describe and discuss the components of the atmosphere.
To determine the impact of human activities on the quality and structure of the
atmosphere.
To formulate ways and means to adopt existing air quality measures.
Introduction
What if one morning you went for a jog, and along the way you read an advisory
on a warning sign saying, “Don’t jog, air polluted. Jog at your own risk!” Does it sound
silly to think that this may one day happen?
In August, 2004, then
Health Secretary Manuel Dayrit
cited results from a study
conducted from January to May,
2003 involving the quality of air in
Metro Manila. The study indicated
that areas where air pollution is
highest, cases of respiratory
diseases also increased. Dayrit
affirmed that there is a direct
relationship between air quality and
the people’s health, “if you live in a place where the air is bad outside, then you are also
affected indoors. Outside, you could be inhaling lead mostly from motor vehicles. This
affects the nervous system. You could also be affected by particulates that could get into
the respiratory tract and can cause bronchitis.”
Other cited respiratory illnesses linked to bad air were cough, colds, chest
tightness, wheezing, sinusitis, acute bronchitis, pneumonia and asthma. Motor vehicles
were reportedly the major source of particulate pollution in Metro Manila areas. Areas
that were highly exposed to air pollution were Caloocan, Valenzuela and Quezon City.
The report even went to say that “those who jog in the polluted areas of Quezon City may
be doing more damage to their health due to the presence of pollutants.” When asked for
what kind of advisory Dayrit may give out, he suggested a warning sign with the advisory
mentioned above. (Manila Bulletin Online, 2006 – See Appendix A for details of this
report)
However, human health is not the only victim of air pollution. For us to determine
what else is affected we must understand first what the atmosphere is and how it
contributes in sustaining life here on Earth. This will also help us identify major human
activities that inflict damage on the atmosphere.
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Natural Science 13
DLS – College of Saint Benilde
Nature and Function of the Atmosphere
It is a mixture of gases surrounding the Earth.
78% nitrogen
21% oxygen
01% carbon dioxide, methane, nitrous oxide
Layers of the atmosphere, where each layer blend into each other (Fig.9-1).
1. Troposphere
 Closest to the lithosphere
and hydrosphere, and is the
most dense among the
other layers of the
atmosphere.
 Extends about 8 miles
from the Earth’s surface.
 Contains: air we breathe,
our weather systems.
 Where greenhouse effect
occurs.
2. Stratosphere
 Extends from 8 to 30
miles.
 Where ozone is formed.
 Where most UV light is
filtered out.
Figure 9-1. Layers of the atmosphere. How far does
the atmosphere stretch into space? In what layer of the
atmosphere is it hottest? (Diagram downloaded using
the Google search engine)
3. Mesosphere
 Extends about 30 to 50 miles.
 Absorbs gamma and X-rays.
4. Thermosphere
 Farthest from the Earth.
 Stretches out from 50 to 600 miles.
 Absorbs gamma and X-rays.
What is an Electromagnetic Spectrum?
It is the entire range of radiation (or energy) produced by the sun.
It interacts with the atmosphere.
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Natural Science 13
DLS – College of Saint Benilde
It consists of the following radiation (Fig.9-2).
Gamma rays
X-rays
Ultraviolet (UV) rays
Visible light (ROYGBIV)
Infrared
Microwave
Radiowave
Figure 9-2. The electromagnetic
energy is the ray that comes from
the sun and reaches the biosphere.
However, not all of its parts reach
the biosphere. From the illustration,
determine what radiation of the
sun’s rays reaches the biosphere?
Why do you think these are the only
ones allowed by the atmosphere?
(Diagram downloaded using the
Google search engine)
Air Pollution
Presence of impurities in the atmosphere which have negative effects on organisms
and their habitats.
Major sources: combustion, evaporation and friction.
Kinds of pollutants:
1. Outdoor pollutants.
2. Indoor pollutants.
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Natural Science 13
DLS – College of Saint Benilde
Major air pollutants and their sources.
MAJOR POLLUTANTS
Carbon monoxide
Formaldehyde
Paradichlorobenzene
Methyl chloride
Tetrachloroethylene
Ammonia
Hydrocarbons
Asbestos
Particulates
Bacteria, fungi
SOURCES
Cigarette smoke, stoves/heaters, automobiles
Particle board, furniture, carpeting, foam insulation
Mothballs
Paint thinner
Dry-cleaning fluids
Cleaning agents
Solvents, adhesives
Insulation, fire proofing materials
Cigarette smoke, pollen, burning wood, coal
Heating/cooling ducts
Smog
Smoke + fog.
Also known as air pollution or dirty air.
A combination of chemicals that may result in a murky, brown haze.
Components of smog:
COMPONENTS
Carbon Monoxide
Hydrocarbon
Lead
Nitrous Oxides
Ozone
Particulate Matter
Smoke
Soot
Sulfur Dioxide
DESCRIPTION
Colorless, odorless, highly poisonous gas. Formed by the increased
burning of fossil fuels.
Also known as volatile gas compounds (VOCs) . Produced by chemical
plants, dry cleaners, gas pumps, automobiles, bakeries (yeast), source
of photochemical smog.
Heavy metal particulate; results mainly from the use of leaded
gasoline; also from paints, metal refineries, and the manufacture of
lead storage batteries.
Group of gases from power plants, metal refineries and automobiles; a
major source of photochemical smog.
A sharp smelling, pale-blue gas consisting of three oxygen atoms.
Solid and liquid pollutants that exist as very small particles light
enough to remain in the air. Includes dust, soot, ash, metals, mists and
sprays.
A form of air pollution consisting of particulate matter.
A fine dispersion of black particles produced by increased combustion.
Colorless gas emitted largely by industrial sources. It is the main cause
of acid rain.
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Natural Science 13
DLS – College of Saint Benilde
Photochemical Smog
A kind of smog caused by chemical reaction in the air. The electromagnetic energy
from the sun causes the chemical reaction.
Reaction:
NOx + O2 SUNLIGHT
O3 (Ozone)
Inversion Layer (or Temperature Inversion)
A layer of warm air (in the atmosphere) lies over a
layer of cooler air, trapping pollutants at ground
level.
Due to geographical and meteorological conditions
like mountainous areas and cold weather (Fig.9-3).
The Clean Air Act
It is a federal law in the USA that forms the basis for
the national air pollution control effort.
This act includes national air quality standards for
major air pollutants, air toxic standards, acid rain
control measures, and enforcement provisions.
This is an example of laws other countries may set
in their respective territories.
Figure 9-3. Inversion layer
threatens human health. In what
way? (Image downloaded using
the Google search engine)
Ozone (O3)
A gas made up of
molecules that have
three oxygen atoms.
Mainly produced in
the stratosphere.
Process of formation:
Sun’s electromagnetic
energy cause normal
oxygen molecules (O2,
oxygen molecule we
inhale) in the
atmosphere to bond
with a single oxygen
atom (Fig.9-4).
Figure 9-4. Ozone molecules form in the atmosphere to create the ozone
layer. This layer protects us from the harmful UV rays of the sun.
(Diagram downloaded using the Google search engine)
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Natural Science 13
DLS – College of Saint Benilde
Concentration of this gas is called Ozone Layer, which shields the Planet Earth from
UV radiation.
Depending on its location, sometimes referred as:
Good Ozone – produced in the stratosphere forming the Ozone Layer.
Bad Ozone – major component of photochemical smog and is formed
when air pollutants (such as NOx) and oxygen, plus sunlight, interact.
Ozone depletion:
- Decrease in the amount of ozone in the stratosphere.
- Sometimes referred to as the thinning or “hole” in the ozone.
- Caused by human activities that involve release of CFCs, or
chloroflourocarbons (Fig.9-5).
Figure 9-5. The diagram above demonstrates how CFCs contribute in destroying ozone
molecules in the atmosphere. With low concentrations of ozone molecules in the atmosphere
it results in the thinning of the ozone layer. (Diagram downloaded using the Google search
engine)
Montreal Protocol:
- An international policy to reduce worldwide CFC emissions.
- Formerly known as the Montreal Protocol on Substances that Deplete the
Ozone Layer.
- This protocol was signed by the world’s leading CFC-producing nations at
Montreal, Canada in 1987.
- After two more meetings (due to further research findings) the nations agreed
to phase out CFCs and other ozone-destroying chemicals.
Greenhouse Effect
Normal warming of the Earth.
Due to trapping of heat energy by certain greenhouse gases in the atmosphere.
A natural process to keep the temperature of the planet habitable.
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Natural Science 13
DLS – College of Saint Benilde
(b)
(a)
Figure 9-6. The greenhouse effect is a normal phenomenon in the biosphere. (a) A normal
greenhouse tends to trap a portion of the heat from the sun to help regulate temperature thereby
aiding plants grow in cold countries. (b) Similarly, the earth is capable of such a mechanism to
regulate global temperature. What do you think will happen if this mechanism is enhanced, or
hastened? (Diagrams downloaded using the Google search engine)
Greenhouse gases:
GREENHOUSE GAS
DESCRIPTION
Carbon Dioxide
Chlorofluorocarbons (CFCs)
Methane
Nitrous Oxides

A group of gases consisting of chlorine,
fluorine and carbon atoms.
 The only greenhouse gas that is not naturally
produced.
 Its primary use: refrigerants and aerosol
propellants.
 Has the greatest ability to trap infrared radiation
compared to other greenhouse gases.
A natural gas produced from:
 Stomachs of cattle
 Burning of fossil fuels
 Termite activities
 Decomposition of landfills (garbage)
 Laughing gas
 Used as dental anesthetic
 Results mainly from nitrogen-based fertilizers
 Also produced by vehicles and industrial
processes
Trace gases
Water Vapor
Enhanced greenhouse effect:
- Increased amount of greenhouse gases in the atmosphere.
- Cause greater retention of infrared radiation.
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Natural Science 13
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DLS – College of Saint Benilde
Increase is due to:
1. Burning of fossil fuels.
2. Deforestation.
3. Use of nitrogen-based fertilizers.
4. Raising cattle.
5. Decomposition of garbage in land fills.
6. Use of refrigerators and air conditioners.
Global warming
- Gradual warming of the Earth as a result of the enhanced greenhouse effect.
Earth Summit:
- Meeting of world leaders in 1992 at Rio de Janeiro, Brazil.
- Discussed only environmental issues, including global warming.
END
References:
Bush, M.B. 1997. Ecology of A Changing Planet. Prentice Hall, Upper Saddle River, New
Jersey, USA.
Brewer, R. 1994. The Science of Ecology, 2nd Ed. Saunders College Publishing, USA.
Cunningham, W.P. and Cunningham, M.A. 2006. Principles of Environmental Science, 3rd
Edition. McGraw-Hill Companies. New York, USA.
Enger, E. and Smith B. 2006. Environmental Science: A Study of Interrelationships, Tenth
Edition. McGraw-Hill Companies, Inc. New York, USA.
Web sites:
The Manila Bulletin Online
http://www3.mb.com.ph/issues/2004/08/19/MTNN2004081916659.html
Hand-out 9: The Atmosphere
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Natural Science 13
DLS – College of Saint Benilde
APPENDIX A
Respiratory diseases linked to city pollution
By Jenny F. Manongdo
Respiratory diseases have increased over the past year due to highly polluted air in Metro
Manila, the Department of Health (DoH) reported yesterday.
Health Secretary Manuel Dayrit cited the Public Monitoring Study of the Metro Manila
Air Quality Improvement Sector Development Program supported by the Asian
Development Bank (ADB).
The study presented the high, medium and low risk areas for exposure to air
pollution.
Dayrit said that there is a direct relationship between air quality and the people’s
health.
"If you live in a place where the air is bad outside, then you are also affected
indoors. Outside, you could be inhaling lead mostly from motor vehicles. This affects
the nervous system. You could also be affected by particulates that could get into the
respiratory tract and can cause bronchitis."
He also highlighted smoking as a household health risk that can contribute to
respiratory problems.
The study listed Caloocan, Valenzuela and Quezon City as areas highly exposed to air
pollution while Pasig, Pateros and Taguig fall under the medium risk areas.
Antipolo was solely considered as an exposure with the lowest exposure to air
pollution. Professor Elma Torres of the University of the Philippines (UP) Public Health
said that Antipolo has a low prevalence of air pollution because it is far from Metro
Manila while Valenzuela is on the high level because it is an industrial zone.
The study was done from January to May 2003, and indicated that motor vehicles
are the major source of particulate pollution in Metro Manila areas highly exposed to
air pollution also have more cases of persons with cough, colds, chest tightness and
wheezing.
Similarly, these areas have a large number of persons with respiratory diseases such
as sinusitis, acute bronchitis, pneumonia and asthma.
The DoH reported 694,836 cases of bronchitis nationwide in 2001. The study said
that in 2002, there is a 10,000 excess cases of the disease that may be attributed to
air pollution," Torres said.
Dayrit recommended the installation of monitoring equipment for the quality of air in
the country.
If the equipment prompts unhealthy air levels, then advisories will be put up in areas
where air pollution is at its peak.
But Dayrit said that level of air pollution varies according to time of the day.
It is highest during the day where there are a lot of vehicles moving and industries
that are operating.
Hand-out 9: The Atmosphere
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Natural Science 13
DLS – College of Saint Benilde
He said that advisories are important to preserve the health of the people.
Those who jog in the polluted areas of Quezon City may be doing more damage to
their health due to the presence of pollutants.
Asked what kind of advisories he may give out, Dayrit said that a warning sign may
be placed in these areas that may likely say "Don’t jog, air polluted. Jog at your own
risk."
http://www3.mb.com.ph/issues/2004/08/19/MTNN2004081916659.html
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