The Science of Climate Change
- Warming over the 20th century is indisputable and largely due to human activities.
- Canada’s rate of warming is about twice the global rate: a 2ºC increase globally means a 3 to 4ºC increase for Canada.
- Effects will persist for centuries because greenhouse gases (GHGs) are long-lived and the oceans are warming.
- Cumulative CO2 emissions largely determine ultimate warming. A 2ºC warming target may still be attainable, but we are already 65% of the way to the associated carbon limit or budget and global emissions must peak before mid-century.
- GHG emissions need to become net zero in order to stabilize climate at any temperature.
Graphic Source: Environment and Climate Change Canada
November 23, 2015