ABSTRACT
The nature of the geophysics and ecosystems of North America leads inescapably to transboundary pollution flows. Environmental dependence is not an automatic and inevitable determinant of policies or outcomes. Canada became the demandeur in 1977 when federal environment minister Romeo LeBlanc gave a historic speech in which he termed acid rain an “environmental time bomb.” In 1979, the United States and Canada joined a large group of European countries in signing the Convention on Long-Range Transboundary Air Pollution, negotiated under the auspices of the United Nations Economic Commission for Europe. Ground-level ozone is a so-called secondary pollutant that results from the reaction of nitrogen oxides and volatile organic compounds in the troposphere, promoted by sunlight and warm temperatures. Particulate matter is the emerging issue in Canada-United States air quality relations in the early 21st century.
