backgrounder
Cars and Trucks and Global Warming
Motor vehicles are
responsible for almost a quarter of annual US emissions of carbon
dioxide (CO2), the primary global-warming gas.
The US transportation sector emits more CO2 than all but three other countries' emissions
from all sources combined. And motor vehicle emissions will continue
to increase as more vehicles hit America's roads and the number of
miles driven grows.
Three factors contribute to CO2 emissions from cars and
trucks:
- Amount of fuel
used
- Amount of CO2 released when a particular fuel is
consumed
- Number of vehicle miles
traveled
Combating global warming requires reducing all of these
factors. This necessitates increased fuel efficiency, switching to
renewable fuels, and less driving.
Increase Fuel
Efficiency
The amount of fuel consumed
by motor vehicles governs how much CO2 pollution enters the atmosphere: the more
gasoline burned, the more CO2 released.
Automobiles need to become more fuel efficient. For the last decade,
however, the fuel-economy standards for motor vehicles have
stagnated. In addition, low gas prices have helped create a market
for gas-guzzling light trucks such as sport-utility vehicles (SUVs)
and minivans, which have actually led to an increase in CO2 emissions.
Increasing fuel efficiency is a
cost-effective and technologically feasible method to address the
threat of global warming, benefit our economy, and protect public
health. To do this, government policies
must:
- Strengthen
fuel-efficiency standards (CAFE) for all passenger vehicles and
eliminate the light-truck (SUV)
loophole.
- Support the development
and marketing of advanced vehicles,
 like battery electrics, hybrid electrics, and fuel
cells. Switch to Renewable
Fuels
Using conventional,
gasoline-combustion technology can only decrease CO2 pollution so much. The large-scale CO2 savings that are necessary require a shift to
renewable fuels. These fuels, because they are not produced from
high-carbon fossil fuels, have lower carbon emissions. To encourage
this shift, government policies should:
- Provide incentives for
research and development of renewable
fuels
- Encourage investment in
renewable fuels and the necessary
infrastructure through methods like tax incentives
Reduce
Driving
With the number of cars on the
road expected to double, gains in fuel efficiency alone will not
reduce CO2 pollution. Measures that reduce
vehicle miles (VMT) traveled also improve the quality of life and
protect natural resources. To reduce VMT, government policies
should:
- Promote
transit-oriented, compact
development
- Provide transportation
alternatives to cars, including
mass transit, bicycle, and pedestrian
routes
- Adopt "fix-it first"
policies to improve existing infrastructure and
roads
|
Cars
and SUVs
