Environmental Engineering Reference
In-Depth Information
100%
1985
1990
1995
2000
80%
60%
40%
20%
0%
Any
standard
basin-day
Ozone*
(1-hour)
Carbon*
monoxide
(8-hour)
PM10*
(24-hour)
FIGURE 2
Percentage of days exceeding federal health standards, South Coast Air Basin (Cal-
ifornia), 1985-2000. ∗: percentage of days exceeding at site with highest
exceedences. (South Coast Air Quality Management District)
centration of ozone in Southern California's skies.As can be seen in figure 1,
the number of days when one-hour ozone concentrations exceeded the
federal standard declined from more than 200 in 1977 to fewer than 50 in
2000. Encouraging gains have also occurred in the reduction of other pol-
lutants. As figure 2 indicates, along with experiencing a decrease in ozone,
Southern California has seen substantial progress in the reduction of car-
bon monoxide and PM10 particulates (particles with diameters of 10
microns or less).
PUBLIC POLICY AND THE REDUCTION OF AUTOMOTIVE EMISSIONS
A substantial portion of these gains can be attributed to a set of technolog-
ical fixes that have dramatically lowered automotive emissions. But these
fixes were implemented because the federal government and the govern-
ment of California made clean air a major policy objective.
2
Government
initiatives were essential for addressing the problem of poor air quality
because individual efforts will never produce cleaner skies. Air pollution is
the classic example of a “negative externality,” that is, a market transaction's
