Environmental Impact of Cars |
|
For much of the early history of the
car, no consideration was given to
various environmental effects caused by the
automobile.
American cars and trucks are a huge source
of global warming pollution.
U.S. autos emit more than 333 million tons of
carbon dioxide each year, more than one-fifth of
the nation's total carbon dioxide emissions.
Compared with the rest of the world, American
auto emissions are disproportionately high. With
only 5 percent of the world's population and 30
percent of the world's automobiles, the United
States contributes 48 percent of the world's
automotive CO2 emissions.
Any serious effort to fight global warming must
include cutting auto emissions.
|
Environmental Effects Include:
(click each for more information)
|
|
|
|
|
|
Energy
Use |
Each year, the United States produces about 10%
of the world's petroleum but consumes about 26%
of the world's total production. Cars and light
trucks are the single largest users of
petroleum, consuming about 43% of the total.
Overall, cars and light trucks consume about 16%
of the total energy used in the U.S.
|
|
Air Pollution |
|
Although great strides have been made at
reducing air pollution from automobile exhaust
over the past 30 years, on-road motor vehicles
still account for a significant proportion of
air pollution:
|
Air Pollutant |
Proportion from On-road Motor
Vehicles |
Note |
|
Oxides of Nitrogen (NOx) |
34% |
precursor to ground-level ozone
(smog), which damages the
respiratory system and injures
plants |
|
Volatile Organic Compounds (VOC) |
34% |
precursor to ground-level ozone
(smog), which damages the
respiratory system and injures
plants |
|
Carbon Monoxide (CO) |
51% |
contributes to smog production;
poisonous in high concentrations |
|
Particulate Matter (PM10) |
10% |
does not include dust from paved and
unpaved roads, which are the major
source of particulate matter
pollution (50% of the total) |
|
Carbon Dioxide (CO2) |
33% |
thought to be primary contributor to
global warming |
-
Carbon dioxide is the dominant greenhouse gas
that causes global warming.
-
Carbon monoxide, when inhaled, impairs the flow
of oxygen to your brain.
-
Sulphur oxides contribute to respiratory
illness, and aggravate existing heart and lung
diseases.
-
Oxides of nitrogen (NOx) react with compounds in
the air to cause acid rain and ozone (the main
reason for smog).
-
Particulate matter are an established cause of
lung problems, including cancer.
-
Hydrocarbons, in their many forms, irritate the
lung and other tissues, contribute to birth
defects and cause other illnesses including
cancer. Lead damages organs, affects the brains,
nerves, heart, and blood.
|
|
Water Pollution |
|
There are a number of ways automobile use
results in water pollution:
Runoff of oil, dirt, brake dust, deposited
vehicle exhaust, road particles, automotive
fluids, and deicing chemicals from roadways and
parking lots. The effect of this is difficult to
quantify, but a 1996 survey of 693,905 river
miles estimated that urban runoff was the
leading source of impairment for 13% of the
river miles that were impaired. One EPA
researcher estimated the amount of oil and
grease runoff from roads surfaces to be in the
hundreds of thousands of tons per year.
Leaking underground fuel storage tanks. As of
1998, there were approx. 892,000 underground
storage tanks in the US, mostly in gasoline
filling stations. A cumulative total of 1.2
million tanks had been closed, with confirmed
releases (leaks) from 371,000 such tanks.
Improperly disposed of waste fluids, e.g. used
motor oil. One quart of motor oil can
contaminate a million gallons of fresh water.
The US EPA estimates 13.4% of used motor oil is
illegally dumped, while another 10.1% is
landfilled.
|
|
Noise Pollution |
Car and truck noise has become perhaps the
primary source of noise pollution in urban
environments. A Federal Highway Administration
brochure states that a typical pickup truck
going by at 50 mph is four times as loud as an
air conditioner an eight times as loud as a
refrigerator. The Organization for Economic
Cooperation and Development (OECD) estimated in
1980 that 37 percent of the US population was
exposed to "annoying" levels of highway noise
(greater than 55 decibels), while 7% was exposed
to levels that made conversation difficult (> 65
dB).
|
|
Land Use |
Cars require a lot of space. In urban areas,
road surfaces cover about 1/5 of all available
land. Rural roads in 1997 covered an estimated
13,363 square miles of land, an area larger the
state of Maryland. Urban roads covered an
additional 4,012 square miles, an area larger
than Delaware.
|
|
Solid Waste |
Over 11 million automobiles were scrapped in
1996. About 75% of the scrapped material was
recycled, while the remaining 25% was landfilled.
In that same year, an estimated 266 million
tires were scrapped, 76% of which was recovered
and recycled, used as fuel, or exported to other
countries. The 63 million tires that were not
recovered were presumably dumped, adding to the
approximately 800 million tires currently
stockpiled in dumps around the country. These
tire dumps, classified as an "ongoing
environmental hazard" in one EPA report, are
ideal breeding grounds for mosquitoes and a very
serious fire hazard. When a tire dump catches
fire, the burning tire casings emit toxic gases
and are very difficult to put out completely.
Some tires dumps have burned for more than a
year.
|
|
Effects on Wildlife |
|
The primary way people kill wildlife is not by
hunting or trapping, but with their automobiles.
It is estimated motor vehicles kill over a
million animals in collisions every day in the
US.
|
|
Resources |
Most of the data for this page came from two US
Environmental Protection Agency reports,
Indicators of the Environmental Impacts of
Transportation: Highway,
Rail,
Aviation, and Maritime Transport and
Indicators of the Environmental Impacts of
Transportation: Updated Second Edition.
Energy data came from the U.S. Dept of Energy's
Transportation Energy Data Book.
Information on wildlife fatalities came from an
Aug. 1, 2002, article in the Wall St. Journal,
"In the Headlights: As Man and Beast Clash on
Highways, Both Sides Lose" by James P. Sterba
|
|
Road-building |
|
1.
With increased road-building came negative
effects on
habitat for
wildlife, primarily through
habitat fragmentation and
surface runoff alteration. New roads
built through sensitive
habitat can cause the loss or
degradation of ecosystems, and the materials
required for roads come from large-scale rock
quarrying and
gravel extraction, which sometimes
occurs in sensitive
ecological areas. Road construction
also alters the
water table, increases
surface runoff, and increases the
risk of flooding.
Most of the data for this page came from
two US Environmental Protection Agency
reports, Indicators of the Environmental
Impacts of Transportation: Highway,
Rail, Aviation, and Maritime Transport
and Indicators of the Environmental
Impacts of Transportation: Updated
Second Edition. Energy data came from
the U.S. Dept of Energy's Transportation
Energy Data Book. Information on
wildlife fatalities came from an Aug. 1,
2002, article in the Wall St. Journal,
"In the Headlights: As Man and Beast
Clash on Highways, Both Sides Lose" by
James P. Sterba
|
|
|
