Energy and Changes in the Environment - Hydrogen and Fuel Cells: Advances in Transportation and Power - page 66

federal government would join American automakers to produce a new,
super-efficient car.
One of the most significant developments in automobiles was the
emergence of the sport utility vehicle or SUV as a dominant vehicle in the
U.S.
SUVs and light trucks are thought to use too much gas and cause
excess pollution compared to the smaller sedans. Light trucks were exempt
from the 1975 fuel economy legislation since it was argued that farmers
and other workers needed them for business. Actually, many more trucks
are used for the same purposes as cars.
By the 1990s, U.S. carbon emissions were rising while Americans
were spending more time on the road and traveling in more of the least
fuel-efficient vehicles. Minivans, SUVs, and pickup trucks made up about
40% of all vehicles sold in the United States.
By 1999 SUVs were getting larger and larger with some more than
18-feet-long and weighing as much as 12,500 pounds which is about as
much as four mid-sized sedans. Fuel economy was about 10 mpg. The
average fuel economy of all cars and trucks in the United States in 2003
model year remains at about the same level since the decade of the 1990s.
EMISSION TARGETS
Today's automobiles may be up to 96% less polluting than cars 35
years ago but automobiles still produce a quarter of the carbon dioxide
generated annually in the United States.
A global accord on reducing hydrocarbon emissions was reached at
the 1992 Early Summit in Brazil but only Great Britain and Germany came
close to meeting their 2000 targets. The United States was short of its goal
by 15 to 20%. This was a commendable effort at international cooperation
but almost every country is filling its roads with more and more autos.
The international agreement on global warming signed by 150
countries in Kyoto, Japan, in 1997 required a drastic reduction in
automobile exhaust emissions. Greenhouse gases were to be reduced to
5.2% below 1990 levels by 2012.
Objectors to Kyoto say it is based on questional science and would
damage the U.S. economy. It exempts two of the world's biggest polluters,
China and India, which together produce about as much CO 2 as the United
States.