Environmental Engineering Reference
In-Depth Information
emissions across the 50 US states. In order to overcome the problem of
comparability and quality of available environmental data, they moved
away from developing countries and used data from the 50 US states.
They also used state-level emissions for the seven major air pollutants
(greenhouse gases, air toxics, carbon monoxide, nitrogen oxides, sulphur
dioxide, volatile organic carbon and particulate matter). They estimated
the relationship using a panel data set consisting of the dif erent states
over time. In addition, access to technology and air pollution control
regulations were likely to be the same across the United States, or at
least the dif erences would be less than that across dif erent countries.
The income data used were expressed in thousands of 1982 US dollars.
They arrived at two main i ndings. First, all seven pollutants decreased
with increase in income even when industrial composition and popula-
tion density/urbanization were controlled for. Second, high-income states
had low per capita emissions while emissions in low-income states were
highly variable. They attributed this i nding to two main factors. First,
richer countries produced goods using less polluting technology per unit
of output, either in the form of designing technology for this purpose or
using the latest technology, which was usually ei cient in terms of energy
consumption. Second, consumers demanded more environmental quality
as they became wealthier, such as shifting their consumption to less pollut-
ing products, moving to cleaner areas or demanding that their government
strictly regulate the output of pollution.
De Bruyn et al. (1998) examined the relationship between economic
growth rate and environmental quality for the Netherlands, West
Germany, the United Kingdom and the United States for various time
intervals between 1960 and 1993. They used emissions data for CO
2
,
NO
x
and SO
2
. The CO
2
emissions data were taken from the Oak Ridge
National Laboratory (1994), while the SO
2
and NO
x
data were taken
from the US Environmental Protection Agency (
National Air Quality and
Emission Trends Report
, 1984) and OECD (
Environmental Data Report
,
1993). They found a positive and signii cant ef ect of economic growth on
the growth of emissions in all of the cases, with the exception of SO
2
in
the Netherlands. The analysis suggested that in only half the cases was the
rise in income the reason for the reduction of emissions. They also found
a positive correlation between time patterns of emissions and economic
growth. The authors concluded that there was no evidence in their country
analysis to coni rm that economic growth would improve environmental
quality. However, the relationship between income and emissions that
could be reduced by using cleaner technology would follow an inverted
U-shaped pattern when using panel data. The decline in emissions over
time would be due to technological and structural changes.
