Green Commercial Vehicle Program

Greenhouse Gases and Climate Change

Greenhouse gases (GHG) are invisible gases in the atmosphere that trap energy from the sun. Naturally occurring GHG include water vapour, ozone, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Without them, the Earth's average temperature would be about 33°C lower than it is, making the climate too cold to support life (Schneider, 1989. Google Book Search, Encyclopedia of Environmental Science, page 303).

While these naturally occurring gases make life possible, of concern is the impact of increased levels of some of these gases, particularly carbon dioxide, in the atmosphere, due mainly to human activities. Too much heat is being trapped and the planet's overall temperature is rising. This is known as global warming.

Global warming is affecting weather patterns all over the world. Changing climates pose risks to the health and safety of people, wildlife, forests, farms and water supplies. The transportation sector accounts for one-third of Ontario's GHG emissions (Natural Resources Canada). This is why it's important for us to take action to stop it.