Environmental Engineering Reference
In-Depth Information
are not identical. Whereas the notion of environmental protection gives precedence
to the idea of preserving natural resources because of their intrinsic value, central to
most definitions of sustainability is the notion of responsibility towards future gen-
erations. Because resources (both natural and manmade) can sometimes be substi-
tuted, the obligation to future generations does not necessarily require that specific
resources should be left untouched, provided that suitable substitutes are provided for
the well-being of future generations (Solow, 1991).
4
In line with established definitions, aviation might be considered sustainable on
account of its contribution to the development of a sustainable global economy, meet-
ing today's needs while investing in the future. This means that aviation activity is
sustainable to the extent that the global socio-economic benefits it provides are not
denied to future generations and its environmental impact is kept within limits
acceptable to society (ATAG, 2002).
Current policy-making tends not to emphasize this theme. Rather, it is oriented
more towards the premise that the continued growth in aviation activity per se is
unlikely to be sustainable without major improvements in environmental perfor-
mance, particularly when compared to other modes of transport. As long as this per-
ception persists, aviation environment policy-making will continue to focus upon
reducing the level per unit of aviation activity of resources consumed, materials
used, wastes generated and pollutants released.
Risk management
Clearly, aviation has a range of atmospheric and climate change impacts that should
be accounted for in the assessment of sustainable development options
.
Because these
impacts are not well understood, but could cause potentially serious and possible irre-
versible changes in the atmosphere and in the global climate, two well-established
principles of international law (though much less accepted in the US than in Europe)
drive environmental risk management and subsequent policy-making. These are that,
first, prevention of environmental damage is better than the remedy (irrespective of
whether there is full scientific proof) and, second, the polluter should pay and dam-
age should be rectified at source (UNCED, Rio Declaration, 1992).
5
The so-called precautionary and polluter pays principles have become the foun-
dations of environmental policy-making generally, but only address the environ-
mental dimension of sustainability. Measures based upon these principles are meant
to reflect a comprehensive, systematic analysis of the problems being addressed,
including the feasibility and (as regards the precautionary principle) the cost effec-
tiveness of any appropriate measures. They are also meant to give due regard to any
potential distortion to the public interest, international trade and investment (the
polluter pays principle). Any resulting policies should be in proportion to the iden-
tified damage; non-discriminatory; consistent with existing measures; and subject to
periodic review.
In practice, these elements have received the least attention at policy-making level.
Instead, the precautionary and polluter pays principles have become a 'catch all' for
environmental policy-making overall, especially in matters of impact prevention and
mitigation. In particular, they have explicitly encouraged the development of poli-
cies designed to address the external effects of specific economic activities.