Download air pollution

How Would You Like to
Live Like This?
Distribution of Global Aerosols
Animation
https://www.youtube.com/watch?feature=playe
r_embedded&v=YtJzn8A725w
What is the atmosphere?
The Earth is different than the other planets
in our solar system because it has an
exosphere
atmosphere that can support life.
thermosphere
The atmosphere is an envelope of
different gases (air) surrounding
Earth.
The atmosphere is divided into five
major layers.
These layers are divided based on
temperature. As you move through the
troposphere the temperature decreases.
mesosphere
stratosphere
troposphere
Our Atmosphere
Air pressure and the troposphere
80% of atmospheric gases are in the troposphere: the
15 km of the atmosphere closest to Earth. This is a very
thin layer compared to the Earth’s diameter, which is
12,756 kilometers.
Atmospheric gases are made up
of tiny particles, each of which
exerts pressure in all directions.
Higher up in the atmosphere,
there are fewer particles, which
causes a decrease in air pressure.
Nearly all weather takes place
in the troposphere.
What is the atmosphere made of?
The gases that make up the atmosphere are:
about 21%
is oxygen
about 78%
is nitrogen
the remaining
1% is mostly
argon (0.93%)
with some
carbon dioxide
(0.035%),
varying amounts
of water vapor
and trace
amounts of other
gases
What is Albedo
• The ability to reflect solar energy is referred to as
albedo.
• Rough textured, irregular, and dark-colored materials
have a low albedo, making them good absorbers of
solar radiation.
• Uniform and light-colored materials such as snow,
water at low sun angles, and sandy soils have a
higher albedo and reflect more solar radiation, thus
absorbing less energy.
Which surfaces will have the
highest albedo values?
How does sun affect temperatures at
different latitudes?
.
Effect of axial tilt on
incoming
solar radiation
Sun angle determines
the intensity of
energy.
What Determines Seasons?
Click on the picture below to see why we have different seasons.
What is heat transfer?
The Sun is the external source of energy for Earth.
Energy reaching Earth drives
global interaction between
the atmosphere and the
surface, creating wind and
influencing ocean currents.
Heat is transferred by
three main processes:

conduction

convection

radiation
Conduction, convection and radiation
Convection is the transfer of heat
energy by the movement of matter.
For example, in a saucepan on the
stove there is a steady flow between
the warm and cool sections of a
fluid. This is a convection current.
Radiation is the transfer of heat energy by electromagnetic
radiation. For example, energy from the Sun travels to Earth
by electromagnetic waves.
Conduction is the transfer of heat energy by direct contact,
or from particle to particle. For example, a spoon in a bowl of
soup becomes warmer because the heat from the soup is
conducted along the spoon.
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© Boardworks Ltd 2009
Differential heating
Radiation from the Sun
does not hit Earth
everywhere at the same
time and in equal amounts.
This means that some places
receive more heat while others
receive less heat. This is
known as differential heating.
Many factors, such as altitude
and latitude, affect the amount
of radiation reaching an area.
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© Boardworks Ltd 2009
• Winds move from high pressure to low
pressure.
• Winds are named by the direction they
blow from
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© Boardworks Ltd 2009
Coriolis effect
https://www.youtube.com/watch?v=mcP
s_OdQOYU
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© Boardworks Ltd 2009
Global wind currents
The global pattern of wind currents can be shown by the three
cell model of air circulation. This shows:
polar easterlies
convection cells (formed
due to differences in high
and low pressure)
deflected winds (due
to the Coriolis effect)
This forms three main wind
patterns in each hemisphere.
westerlies
trade winds
westerlies
polar easterlies
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© Boardworks Ltd 2009
Outdoor Air Pollution
Primary Pollutants
CO
SO2
CO2
NO
NO2
Most hydrocarbons
Most suspended
particles
Natural
Stationary
Mobile
Secondary Pollutants
SO3
HNO3
H2O2
SO4
–
H2SO4
O3
Most NO3 and
PANs
2–
salts
Criteria Pollutants monitored
closely by the EPA
Carbon monoxide (CO)
Sulfur dioxide (SO2)
Nitrogen dioxide (NO2)
Tropospheric ozone (O3)
Particulate matter (soot, dust, sulfates, nitrates, etc)
Lead (enters as a particulate pollutant)
https://airnow.gov/
What are the Consequences of
Some Daily Activities?
Air Pollutant
Corresponding color/mix
Sulfur dioxide (SO2)
Pinch of lemonade mix
Nitrous Oxides (NOx)
Pinch of cocoa drink mix
Carbon Monoxide (CO)
One drop red food coloring
Lead (Pb)
One drop green food coloring
Volatile Organic Compounds (VOCs)
One drop blue food coloring
Particulate Matter (PM)
Pinch of ground charcoal
Ozone (O3)
One drop yellow food coloring
What is Your Air Quality?
If the air pollution around you were this apparent,
would you want to breathe the air?
What other sources of air pollution beyond those
mentioned in this demonstration, could you think of as
being produced in a single day?
How is our air a “commons”?
How is this demonstration an example of the “Tragedy
of the Commons?”
What could you do to reduce your impact on the air we
all breathe?
Clean Air Carolina
Examples of Particulates
and Relative Size
• www.cleanaircarolina.org
• https://www.youtube.com/
watch?feature=player_emb
edded&v=n2AjfYilS88#t=23
• https://airnow.gov/inde
x.cfm?action=movies.in
dex
Photochemical Smog
• Photochemical smog is a
mixture of air pollutants
formed by the reaction of
nitrogen oxides and volatile
organic hydrocarbons when
they are exposed to sunlight.
• More than 100 primary and
secondary pollutants can be
formed.
Photochemical Smog (brown air smog)
F
Photochemical Smog
VOC + NOx + heat + sunlight
ground level ozone (O3)
+ other photochemical
oxidants
+ aldehydes
+ other secondary air
pollutants
Industrial Smog – Gray Air Smog
Particulates
Sulfur Dioxide
Sulfuric Acid
China’s Air Pollution Problem
http://www.youtube.com/watch?v=G
sjANjFlK0M
http://www.cbsnews.com/news/pollu
tion-from-china-alters-weather-in-uswest/
Temperature Inversions
During daylight hours, the sun warms the ground
which warms the air near the Earth’s surface.
The warm air rises as more dense cool air
displaces it. Any pollution in the air normally
disperses in the turbulence caused by the mixing
of the air. Temperature Inversion occurs when a
layer of warm air traps the layer of cool air near
the Earth’s surface. Pollutants are not dispersed
but continue to build up in the still, stagnant air.
Temperature Inversions
http://www.youtube.com/watch?v=EKW0bW1WVEY
Los Angeles
Descending warm air mass
Increasing altitude
Inversion layer
Sea breeze
Mountain
range
Decreasing temperature
Sea breezes keep the air and pollution onshore,
and the mountains prevent the air from escaping.
The cold air aloft acts as a lid.
Emission Reduction
Electrostatic Precipitator
Cleaned gas
Electrodes
Dust discharge
Dirty gas
Bags
Baghouse Filter
Cleaned gas
Dirty gas
Dust discharge
Cleaned gas
Dirty gas
Cyclone Separator
Dust discharge
Cleaned gas
Dirty gas
Clean
water
Wet
gas
Dirty water
Wet Scrubber - Remove 98% of SO2 and particulate matter
Solutions
Motor Vehicle Pollutions
Prevention
Mass transit
Bicycles and walking
Less polluting fuels
Get older, polluting
cars off the road
Give buyers tax writeoffs for buying lowpolluting, energyefficient vehicles
Cleanup
Emission control
devices
Improve fuel efficiency
Less polluting engines
Car exhaust
Inspections
twice a year
Restrict driving in
polluted areas
Stricter
emission
standards
Carpooling????
Solutions
Air Pollution
Prevention
Cleanup
Reduce
poverty
Improve energy
efficiency
to reduce fossil fuel
use
Rely more on lowerpolluting natural gas
Rely more on
renewable energy
(especially solar cells,
wind, and solarproduced hydrogen)
Transfer technologies for
latest energy efficiency,
renewable energy, and
pollution prevention to
developing countries.
Reduce or ban
indoor smoking
Develop simple and
cheap test for indoor
pollutants such as
particulates, radon,
and formaldehyde
How Can Laws Be Improved?
 Rely on pollution prevention rather than cleanup.
 Increase fuel efficiency standards for cars, SUVs and light
trucks.
 Regulate the emissions from inefficient 2 cycle engines
(lawnmowers, leaf blowers, jet skis, outboard motors, etc)
 Regulate pollution from oceangoing ships in American
ports.
 Amend the Clean Air Laws to deal with emissions of
carbon dioxide and other greenhouse gases.
 Better enforcement of the Clean Air Act