9/16/2013 1 ES 541 Contemporary Environmental Issues Unit 4 Air pollution Atmosphere as a Resource Atmospheric Composition Nitrogen 78.08% Oxygen 20.95% Argon 0.93% Carbon dioxide 0.04% Ecosystem services Blocks UV radiation Moderates the climate Redistributes water in the hydrologic cycle Life-Air Air? Not Ordinary Air! It is Life-Air from the Skies! • Without ‘Food’ (but ‘Water’) human can live for ‘3 Days’. • Without ‘Water’ (and no ‘Food’) human can live for ‘1 Day’. • Without ‘Air’ (even with ‘Food’ and ‘Water’) human can live for ‘1 Minute’. Ques: Guess, what is ‘Death’? Ans: No Air for ‘1 Minute’ is called as ‘Death’. Air is so important. Pollution is a serious issue. Air is Expensive than Blood Air is what we Breathe every Second, even during Sleep! • Air is sucked into lungs every few seconds and the alveolar system of the lungs helps the oxygenation of blood in every drop. • Heart pumps Blood and Blood carries O 2 (by Hemoglobin) to every part/cell of the body to sustain Life inside. • ‘More O 2 ’ into the body is called ‘More Life’. • Similarly ‘Better O 2 ’ into the body is called ‘Better Life’. • But then ‘Polluted O 2 ’ into the body is called ‘Polluted Life’. THE RESULT OF EMISSION INTO THE AIR OF HAZARDOUS SUBSTANCES AT A RATE THAT EXCEEDS THE CAPACITY OF NATURAL PROCESSES IN THE ATMOSPHERE TO CONVERT, DEPOSIT, OR DILUTE THEM… What is air pollution Factors that affect air pollution Emissions (traffic, industrial, domestic) Geography (terrain) Weather conditions (rain, winds, humidity) Season Time of day Population density Indoor vs outdoor
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9/16/2013
1
ES 541
Contemporary Environmental
Issues
Unit 4
Air pollution
Atmosphere as a Resource
Atmospheric Composition Nitrogen 78.08%
Oxygen 20.95%
Argon 0.93%
Carbon dioxide 0.04%
Ecosystem services Blocks UV radiation
Moderates the climate
Redistributes water in the hydrologic cycle
Life-Air
Air? Not Ordinary Air!
It is Life-Air from the Skies!
• Without ‘Food’ (but ‘Water’) human can live for ‘3
Days’.
• Without ‘Water’ (and no ‘Food’) human can live
for ‘1 Day’.
• Without ‘Air’ (even with ‘Food’ and ‘Water’)
human can live for ‘1 Minute’.
Ques: Guess, what is ‘Death’?
Ans: No Air for ‘1 Minute’ is called as ‘Death’.
Air is so
important.
Pollution is
a serious
issue.
Air is Expensive than Blood
Air is what we Breathe every Second, even during Sleep!
• Air is sucked into lungs every few seconds and the alveolar
system of the lungs helps the oxygenation of blood in every
drop.
• Heart pumps Blood and Blood carries O2 (by Hemoglobin) to
every part/cell of the body to sustain Life inside.
• ‘More O2’ into the body is called ‘More Life’.
• Similarly ‘Better O2’ into the body is called ‘Better Life’.
• But then ‘Polluted O2’ into the body is called ‘Polluted Life’.
THE RESULT OF EMISSION INTO THE AIR OF HAZARDOUS SUBSTANCES AT
A RATE THAT EXCEEDS THE CAPACITY OF NATURAL PROCESSES IN THE ATMOSPHERE TO CONVERT,
DEPOSIT, OR DILUTE THEM…
What is air pollution Factors that affect air pollution
Emissions (traffic, industrial, domestic)
Geography (terrain)
Weather conditions (rain, winds, humidity)
Season
Time of day
Population density
Indoor vs outdoor
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Types of air pollution
Aerosols Particulates solid phase
Dust
Ash
Fumes
Solid and liquid Smoke (from combustion)
Coastal aerosols
Liquid
Aggregate gases (sulfate, nitrate)
Gases COx
SOx
NOx
PAH
Types and Sources of Air Pollution
Two categories
Primary Air Pollutant
Harmful substance that is emitted directly into the atmosphere
Secondary Air Pollutant
Harmful substance formed in the atmosphere when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants
Six primary or “criteria” air pollutants
Carbon monoxide (CO)
Ozone (O3)
Nitrogen dioxide (NO2)
Sulfur oxides (SOx)
PM2.5 and PM10
Lead (Pb)
Major Air Pollutants Air Pollution Around the World
Air quality is deteriorating rapidly in developing countries
Shenyang, China
Residents only see sunlight a few weeks each year
Developing countries have older cars
Still use leaded gasoline
5 worst cities in world
Beijing, China; Mexico City, Mexico; Shanghai, China; Tehran, Iran; and Calcutta, India
Indoor air quality (IAQ) is a term referring to the air quality within and around buildings and structures.
IAQ can be affected by microbial contaminants (mold, bacteria), gases (including carbon monoxide, radon, volatile organic compounds), and particulates.
Indoor air pollution: Poor countries
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Control of Indoor Air Pollution
Basic approaches to control indoor air pollution include source control, source isolation, increased ventilation, dehumidification, and the use of filters. Possible sources of contamination are eliminated in a source-control strategy. Examples include banning smoking in public buildings.
Source-isolation strategy is used in situations where a
source cannot be completely eliminated. For instance,
copy machine areas, food service stations, and
bathrooms are often separately vented outside buildings
to avoid the recirculation of return air.
Main indoor pollutants and their sources
Main indoor air pollutant and their sources,continue
Sources Pollutant
Cigarette and water pipe smoking Environmental
tobacco smoke
Unburned kerosene, gas water
heaters, gas stoves, automobile
exhaust, tobacco smoke
Carbon monoxide
Lead based paints, contaminated
soil, dust and drinking water
Lead
Deteriorating, damaged, or
disturbed insulation, fireproofing,
acoustical materials, and floor tiles
Asbestos
Kerosene heaters, un-vented gas stoves and heaters.
• Ultimate toxicant: • No enzyme can detoxify it • Only protection: prevention of its formation
What’s in smog
particulates (especially lead)
nitrous oxides
potassium
Carbon monoxide
Other toxic chemicals
Acid rain
contains high levels of sulfuric or nitric acids
contaminate drinking water and vegetation
damage aquatic life
erode buildings
Alters the chemical equilibrium of some soils
Acid Deposition
Sulfur dioxide and nitrogen dioxide emissions react with water vapor in the atmosphere and form acids that return to the surface as either dry or wet deposition