Increasing levels of greenhouse gas emissions are warming our planet and driving climate change. How do scientists know this? This page provides a snapshot of some of the key data points and observed trends related to global climate change. References and links provide more in-depth data, trends, and scientific analysis.
Global Average Temperature
Human-induced warming reached approximately 1°C above pre-industrial levels in 2017, increasing at 0.2°C per decade according to Global Warming of 1.5°C, a special report by the Intergovernmental Panel on Climate Change (IPCC)1. Both past and future warming in Canada is, on average, about double the magnitude of global warming. Northern Canada has warmed and will continue to warm at more than double the global rate.2 3
Sixteen of the seventeen warmest years on record have occurred between 2001 and 2018. Scientific research has shown this change is driven primarily by increased carbon dioxide and other human-made greenhouse gas emissions into the atmosphere.
Although the global atmospheric concentrations of carbon dioxide have varied over the millennia, since the industrial revolution in the mid-1700s it has increased to unprecedented levels4.