Global Temperature History
Temperature change since the industrial revolution
The increase in temperature since about 1850 that convinces us that global warming is taking place shows a global temperature increase between 0.5 and 1°C. For perspective, it is important to compare that to longer term temperature models.
This approximate timeline for global temperature is modeled after Marshak. It can provide some context of the range of global temperatures through the warm and cold periods of the past several thousand years.
Marshak, Essentials of Geology