Introduction to Climate Change

1. Introduction to Air Pollution

As industrialization has spread, air pollution has become a major problem throughout the world, particularly in urban centers. The public health consequences of air pollution are well known, and often much greater than other environmental issues, even in developing countries. For example, according to the World Bank, 1.3 billion people live in urban areas that do not meet World Health Organization air pollution standards, resulting in from 300,000 to 700,000 additional deaths each year. Death, of course, is not the only human health impact. Lead poisoning due to air pollution in Bangkok is estimated to have caused a decrease of four IQ points for the average child by the age of seven. Air pollution also causes significant damage to the environment, including buildings, materials and vegetation.

Transboundary air pollution has given rise to some of the most important international disputes, beginning in the 1940s with the well known Trail Smelter Arbitration between Canada and the United States. Trail Smelter involved the relatively simple case of a factory located wholly inside one country (Canada) but near and upwind of the border of another country (the United States).

The rule emanating from Trail Smelter, now widely accepted as customary international law, is that one State should not allow activities under its jurisdiction or control to harm the environment of a neighboring State or of areas beyond national jurisdiction. Trail Smelter and customary international law relating to transboundary air pollution are addressed in Part II of this Chapter.

The impact of long range pollutants came to the fore in the 1970s, particularly with respect to sulfur dioxide (SO2) and nitrous oxide (NOx) emissions and their contribution to acid rain (more properly called acid deposition, because it can occur both as snow and as dust in addition to rain).

Concern over acid deposition has led to significant international negotiations both in North America and in Europe. Europe, under the auspices of the U .N. Economic Commission for Europe, has adopted a complex and comprehensive regime for regulating long range air pollution (known as the Convention on Long-Range Transboundary of Air Pollutants or LRTAP). After agreeing to a framework convention, the parties established a series of separate protocols to control NOx, SO2, volatile organic compounds (VOCs), and persistent organic pollutants (POPs). This treaty regime is important in its own right, but also as a model for the Montreal Protocol regime, the 1992 Climate Change Convention, and the 2001 POPs Convention.