Environmental Engineering Reference
In-Depth Information
Figure 1. CO
2
shares of different country groups
a. The assumption is a stationary analysis rather
than a dynamic one. Although ships may
respond to a fuel price change, for instance,
by adjusting speed or improve in fuel effi-
ciency, such a response is beyond the scope
of this work and would require a much more
complicated operational research.
b. The arrangement that all CO
2
needs to be
purchased in the shipping industry would
be a very stringent regulation in the GHG
reduction. Usually, at least a portion of GHG
emission rights are given away without any
charge, which gives the industry windfall
profits.
that commodity price affects freight rates (Limao
& Venables, 2001; Hummels
et al
., 2007), this
assumption would seem to be valid since aver-
age ship speed has remained roughly constant
in a short term (Lloyds Maritime Information
System, 2007).
Fourth, there are few short term changes in
container fleet size. This too appears to be a valid
assumption given the empirical data. Although
there is no major technological barrier to contain-
erships becoming larger in size, ports and other
infrastructure would need time to adjust to larger
fleets (Notteboom, 2004). Data in the Research and
Innovative Technology Administration shows the
average containership size (calculated as Dead-
weight Tonnage, or DWT) has few increases in
some major U.S. containership ports between the
years 2003 and 2005 (U.S. Department of Trans-
portation Maritime Administration, 2003-2007).
Assumption two to four are related to the fu-
ture scenarios. In other words, the results of the
calculation have future policy implications only
if these assumptions are met.
Second, the average freight rate across dif-
ferent routes remains generally constant in the
short term. This assumption is consistent with the
observations from UNCTAD documenting that
the average freight rates of U.S. ports are stable
with few fluctuations (±15%).
Third, the economic conditions are exogenous
to voyage cost. Though the literature does suggest
Result
Figure 1 reports the CO
2
emissions by country
groups. Non-Annex I countries have the most CO
2
emissions (68%) because of the large number of
voyages. For the economies in transition, although
ships from these countries only accounted for 1%
