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Air, Water, and Soil Pollution
A meta-study conducted in 2007 by
David Pimentel at Cornell
University suggests that as many
as 40% of all deaths worldwide
are linked to soil, water, and air
pollution.
Air pollution from smoke and various
chemicals kills 3 million people a
year worldwide.
In the United States alone about 3
million tons of toxic chemicals are
released into the environment --
contributing to cancer, birth
defects, immune system defects
and many other serious health
problems.
Source: Pimentel, David. Cornell University. 2007.
Water and Air Pollution
Air Pollution / Photochemical Smog
- Ground-level Ozone
- Volatile Organic Compounds (VOCs)
- Particulate Matter (ash, smoke, dust,
pollen)
Soil Contamination
- Acid Deposition/Acid Rain
- DDT
- Heavy Metals
Water Pollution
- Minamata Disease (methylmercury
contamination)
- bioaccumulation
- Eutrophication and Dead Zones (excess
nitrogen)
Air pollution
- Role of physical geography
- Prevailing winds
- Topography and inversions
- Role of cultural geography
- Use of fuels and solvents related to level of
urbanization, industrialization, and regulations
- Disruption of soil linked to particulate matter
Air pollution
- A photochemical smog is the chemical
reaction of sunlight, nitrogen oxides (NOx)
and volatile organic compounds (VOCs) in
the atmosphere, which leaves airborne
particles (called particulate matter) and
ground-level ozone.
- 3 million deaths worldwide
Defining Dirty Air
- Smog is the general term used to describe a variety of air pollutants, including
ground-level ozone (smog's main ingredient), particulate matter, carbon monoxide and nitrogen oxides. It refers to air pollution that is formed when gases from many sources are released into the air and chemically react with each other in sunlight.
- Ocean breezes sweep the smog inland toward the mountains where an inversion
layer of warm air pushes it down, trapping the smog close to the ground where we live and breathe.
Ground-level ozone (O3) is a colorless, odorless pollutant formed by a chemical
reaction between volatile organic compounds (VOCs) and oxides of nitrogen (NOx) in the presence of sunlight. The primary source of VOCs and NOx is mobile sources, including cars, trucks, buses, plus agricultural and construction equipment.
Particulate matter (PM ) is the term used for a mixture of solid particles and liquid
droplets found in the air. It originates from a variety of sources, including motor vehicles, power plants, construction activities, soil dust, soot and industrial processes. Coarse particles (PM10) are generally emitted from sources such as windblown dust, vehicles traveling on unpaved roads, and crushing and grinding operations. Fine particles (PM2.5) can come from fuel combustion (motor vehicles, power generation, industrial facilities) and fugitive dust. PM2.5 is formed primarily in the atmosphere from gases such as sulfur oxides, NOx, and VOCs.
Carbon monoxide (CO) is a colorless, odorless gas by-product of combustion produced
primarily by motor vehicles. Burned wood and charcoal also emit carbon monoxide.
Air Pollutants
Controlling Los Angeles Smog with Technology?
Since smog was first recognized as a serious problem in 1947,
inventors and engineers have proposed innovative ideas to get
rid of it.
- One was to connect all Los Angeles industries to a massive network of
concrete exhaust pipes routed to the mountains where pollution could be released above the inversion layer. If it works for sewage, it will work for air pollution, thought the engineering firm that pioneered the "air sanitation system" concept. But the system would have required 89 miles of ductwork and the energy to move the large volumes of air would have been several times beyond what Hoover Dam could supply.
Many other ideas surfaced in the 1950s and 1960s to purify,
ventilate or wash the air over Los Angeles.
- One was to cut holes in the mountains and install huge exhaust fans to blow
smog out of the basin. However, blowing or washing away smog proved to be impractical since it involved a land mass of 1,600 square miles and over 200 million tons of air. The enormous energy requirements made the idea impossible.
- One scientist suggested blackening whole sections of the eastern mountains
so as to store heat and create thermal currents and westerly winds that would blow smog over the mountains Docsity.com
Particulate matter
- Source: incomplete burning of fuel
- Respiratory problems
- Short transport distance
- Closest to source = most affected
Source: AQMD
Photochemial smog
- Sources: incomplete burning of fuel
- Nitrogen dioxide, hydrocarbons, and
sunlight
- Forms ozone at ground level
- Respiratory problems, damage to plants
link
Historic Smog Levels, Los Angeles
