Environmental Engineering Reference
In-Depth Information
economic efficiency, are relevant considerations. This will be subject to political deci-
sion-making and negotiations.
In order to keep the complexity of the political discussion to a minimum, it is
often focused upon single policy instruments. This may be appropriate as long as sin-
gle policy instruments implemented at the national level work well in solving the
respective environmental problem. However, a limited set of instruments most likely
will prove insufficient in mitigating aviation's climate impact due to the:
•
new and partly still-preliminary evidence on aviation's climate impact and its
likely future dynamics;
•
relatively large number of actors involved;
•
varying economic dependency of countries and regions on aviation services;
•
significant variation in operational conditions within the aviation industry at the
global scale; and
•
need to take globally coordinated or harmonized measures.
In order to deal with these obstacles, a patchwork policy approach that considers
both the full range of options available for reducing aviation's climate impact and a
broad range of policy instruments, to be implemented at the various political levels,
may be most suitable. Only a patchwork of policy instruments will be able to cover
the different political levels involved, and will account for the high level of coordina-
tion needed between national and regional approaches and what are likely to be only
moderately strict individual instruments implemented at the international level. Such
an approach may also allow for more flexibility on the part of individual governments
or certain regions and, hence, help attain more ambitious emission-reduction targets
at the global scale. Moreover, single policy instruments may come along with signif-
icant rebound effects. Therefore, a comprehensive policy package may help to avoid
undesired countervailing effects (ECMT, 1997, p117). An optimum patchwork
would combine policy instruments that are mutually reinforcing. Moreover, com-
plementarity in terms of options used, actors influenced and timing of phasing-in
would yield the biggest overall effect. Table 11.3 provides an assessment of the strengths
and weaknesses of various policy instruments.
In Table 11.3, the assumed strictness of individual policy instruments and the
assessment of their effects reflect existing barriers to implementation and can there-
fore be regarded as an outcome of a political compromise. The assessment of the
effects differentiates between effects on the level of general aviation activity and
effects on GHG intensity of operation. To the extent that strong effects on intensity
give rise to cost reductions, this may result in rebound effects in the form of induced
demand. Some rebound effects on emission intensity may also occur in the form of
higher fuel burn owing to a reduction in flight altitude. Table 11.3 also shows which
instruments address which direct actors. The assessment of the timing differentiates
between the time that will most likely be required to introduce an instrument and to
attain the full effect, respectively. Regarding the geographical scope of implementa-
tion, political levels for implementation are suggested. The last level (global) is the
optimum level for reasons of environmental effectiveness and undistorted competi-
tion. However, policies may start at national or regional levels in a stepwise process
of implementation in order to gain momentum.
