Tailpipe emissions of nitrogen oxides, particulates and carbon monoxide have fallen by more than half.
Since the 1980s, ranges of projection were systematically too high.
In 2017, Canada was responsible for only 1.7 per cent of global carbon dioxide emissions.
Ottawa has layered its carbon tax on top of many existing supports for other forms of energy.
Canada’s contribution of greenhouse gases comprises only 1.6 per cent of global emissions.
Chevron and Occidental are investing in an air capture facility in British Columbia.
Governments could facilitate the use of natural gas to replace diesel fuel and gasoline.